Separate exec types into files, document code (#10)

Reviewed-on: #10

.gitea/workflows/test.yml

@@ -10,24 +10,36 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
+      - name: Checkout repository
+        run: |
+          git clone \
+            "${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git" \
+            .
 
-      - name: Setup Go
-        uses: actions/setup-go@v5
-        with:
-          go-version: "1.22"
+          git checkout "${GITHUB_SHA}"
 
-      - name: Cache Go modules
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cache/go-build
-            ~/go/pkg/mod
-          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+      - name: Verify checkout
+        run: |
+          pwd
+          ls -la
+          test -f go.mod
+
+      - name: Install Go
+        run: |
+          rm -rf /usr/local/go
+          curl -LO https://go.dev/dl/go1.26.2.linux-amd64.tar.gz
+          tar -C /usr/local -xzf go1.26.2.linux-amd64.tar.gz
+          export PATH=/usr/local/go/bin:$PATH
+          go version
 
       - name: Download dependencies
-        run: go mod download
+        run: |
+          go mod download
 
       - name: Run tests
-        run: go test ./... -v
+        run: |
+          go test ./... -v
+    
+      - name: Build binary
+        run: |
+          go build -o app .

cache.go

@@ -1,45 +0,0 @@
-package simpleorm
-
-import (
-	"sync"
-)
-
-type OrmCache struct {
-	mu   sync.RWMutex
-	data map[string]*Table
-}
-
-func NewOrmCache(tables []*Table) *OrmCache {
-	cache := &OrmCache{
-		data: make(map[string]*Table),
-	}
-	for _, table := range tables {
-		cache.add(table)
-	}
-
-	return cache
-}
-
-func (o *OrmCache) add(table *Table) {
-	o.mu.Lock()
-	defer o.mu.Unlock()
-	o.data[table.Type.Name()] = table
-}
-
-func (o *OrmCache) Get(typeName string) (*Table, bool) {
-	o.mu.RLock()
-	defer o.mu.RUnlock()
-	table, ok := o.data[typeName]
-	return table, ok
-}
-
-func (o *OrmCache) GetAll() []*Table {
-	o.mu.RLock()
-	defer o.mu.RUnlock()
-	var result []*Table
-
-	for _, v := range o.data {
-		result = append(result, v)
-	}
-	return result
-}

cache/cache.go

@@ -0,0 +1,47 @@
+package cache
+
+import (
+	"sync"
+
+	"git.gdulai.com/gdulai/simpleorm/schema"
+)
+
+type SchemaCache struct {
+	mu   sync.RWMutex
+	data map[string]*schema.Table
+}
+
+func NewSchemaCache(tables []*schema.Table) *SchemaCache {
+	cache := &SchemaCache{
+		data: make(map[string]*schema.Table),
+	}
+	for _, table := range tables {
+		cache.add(table)
+	}
+
+	return cache
+}
+
+func (o *SchemaCache) add(table *schema.Table) {
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	o.data[table.Type().Name()] = table
+}
+
+func (o *SchemaCache) Get(typeName string) (*schema.Table, bool) {
+	o.mu.RLock()
+	defer o.mu.RUnlock()
+	table, ok := o.data[typeName]
+	return table, ok
+}
+
+func (o *SchemaCache) GetAll() []*schema.Table {
+	o.mu.RLock()
+	defer o.mu.RUnlock()
+	var result []*schema.Table
+
+	for _, v := range o.data {
+		result = append(result, v)
+	}
+	return result
+}

column.go

@@ -1,65 +0,0 @@
-package simpleorm
-
-import (
-	"reflect"
-	"strings"
-)
-
-type Column struct {
-	Name      string
-	FieldName string
-	Type      string
-	Modifiers map[string]string
-}
-
-func NewColumn(name string, typ string, fieldName string, tag reflect.StructTag) Column {
-	return Column{name, typ, fieldName, determineModifiers(tag)}
-}
-
-func determineModifiers(tag reflect.StructTag) map[string]string {
-	modifiers := make(map[string]string)
-	sqlTag := tag.Get("sql")
-	if sqlTag == "" {
-		return modifiers
-	}
-
-	rawModifiers := strings.SplitSeq(sqlTag, ";")
-	for rawModifier := range rawModifiers {
-		if strings.Contains(rawModifier, "=") {
-			keyValue := strings.Split(rawModifier, "=")
-			modifiers[keyValue[0]] = keyValue[1]
-		} else {
-			modifiers[rawModifier] = ""
-		}
-	}
-	return modifiers
-}
-
-func (c *Column) ToDDL() string {
-	var ddlBuilder strings.Builder
-
-	ddlBuilder.WriteString(c.Name + " " + c.Type)
-
-	inlineMods := c.inlineModifiers()
-	for _, mod := range inlineMods {
-		ddlBuilder.WriteString(" " + mod)
-	}
-
-	return ddlBuilder.String()
-}
-
-func (c *Column) inlineModifiers() []string {
-	var mods []string
-	for k, _ := range c.Modifiers {
-		switch k {
-		case "nn":
-			mods = append(mods, "NOT NULL")
-		}
-	}
-	return mods
-}
-
-func (c *Column) IsPK() bool {
-	_, ok := c.Modifiers["pk"]
-	return ok
-}

constraint.go

@@ -1,59 +0,0 @@
-package simpleorm
-
-import "strings"
-
-type Constraint struct {
-	Name       string
-	Type       string
-	Columns    []Column
-	RefTable   *Table
-	RefColumns []Column
-}
-
-func (c *Constraint) ToDDL() string {
-	switch c.Type {
-	case "pk":
-		return c.toPkDDL()
-	case "fk":
-		return c.toFkDDL()
-	}
-
-	return ""
-}
-
-func (c *Constraint) toPkDDL() string {
-	var ddl strings.Builder
-	ddl.WriteString("CONSTRAINT " + c.Name + " PRIMARY KEY(")
-	for i, col := range c.Columns {
-		if i != 0 {
-			ddl.WriteString(", ")
-		}
-		ddl.WriteString(col.Name)
-	}
-	ddl.WriteString(")")
-	return ddl.String()
-}
-
-func (c *Constraint) toFkDDL() string {
-	var ddl strings.Builder
-	ddl.WriteString("CONSTRAINT " + c.Name + " FOREIGN KEY(")
-
-	for i, col := range c.Columns {
-		if i != 0 {
-			ddl.WriteString(", ")
-		}
-		ddl.WriteString(col.Name)
-	}
-	ddl.WriteString(") REFERENCES " + c.RefTable.Name + "(")
-
-	for i, col := range c.RefColumns {
-		if i != 0 {
-			ddl.WriteString(", ")
-		}
-		ddl.WriteString(col.Name)
-	}
-
-	ddl.WriteString(")")
-
-	return ddl.String()
-}

dbconnection.go

@@ -22,6 +22,24 @@ func OpenConnection(driver string, dsn string) *DBConnection {
 	return &DBConnection{db: db, State: 1}
 }
 
+func (c *DBConnection) Exec(sql string) (sql.Result, error) {
+	// Force a real DB interaction
+	result, err := c.db.Exec(sql)
+	if err != nil {
+		log.LogFatalError("DB execution failed: %", err)
+		return nil, err
+	}
+	return result, nil
+}
+
+func (c *DBConnection) Prepare(sql string) (*sql.Stmt, error) {
+	return c.db.Prepare(sql)
+}
+
+func (c *DBConnection) Begin() (*sql.Tx, error) {
+	return c.db.Begin()
+}
+
 func (c *DBConnection) Close() (bool, error) {
 	err := c.db.Close()
 	if err != nil {

exec/count.go

@@ -0,0 +1,96 @@
+package exec
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+// Count represents a count query.
+type Count[T any] struct {
+	target    schema.Table
+	whereStmt string
+	args      []any
+	result    int64
+}
+
+// CreateCount returns a new instance of Count.
+//
+// orm is the simpleorm.ORM instance which connects, caches and manages the relations.
+func CreateCount[T any](orm *simpleorm.ORM, whereStmt string, args ...any) (Count[T], error) {
+	table, ok := orm.Cache().Get(reflect.TypeFor[T]().Name())
+	if !ok {
+		return Count[T]{}, errors.New("Failed to get table from schema cache")
+	}
+
+	return Count[T]{target: *table, whereStmt: whereStmt, args: args}, nil
+}
+
+// Result returns the result of the count query.
+func (c *Count[T]) Result() int64 {
+	return c.result
+}
+
+// Execute executes the parsed count query against a connection and returns an error if there was any during the execution.
+//
+// conn is the simpleorm.DBConnection which handles the database connection.
+func (c *Count[T]) Execute(conn *simpleorm.DBConnection) error {
+	return c.execute(conn, nil)
+}
+
+// execute executes the parsed count query against a connection and transaction and returns an error if there was any during the execution.
+//
+// conn is the simpleorm.DBConnection which handles the database connection.
+// tx is the sql.Tx transaction which the count query will be run in.
+func (c *Count[T]) execute(conn *simpleorm.DBConnection, tx *sql.Tx) error {
+	// Reinit the results, new execution
+	c.result = -1
+	dml := c.target.GetCountDML()
+
+	if c.whereStmt != "" {
+		dml += " WHERE " + c.whereStmt
+	}
+
+	log.LogDebug("Preparing sql: %s, with args: %s", dml, c.args)
+
+	var stmt *sql.Stmt
+	var err error
+	if tx != nil {
+		stmt, err = tx.Prepare(dml)
+	} else {
+		stmt, err = conn.Prepare(dml)
+	}
+
+	if err != nil {
+		return err
+	}
+	defer stmt.Close()
+
+	log.LogDebug("Executing statement: %s", stmt)
+
+	if len(c.args) == 0 {
+		err = stmt.QueryRow().Scan(&c.result)
+	} else {
+		// Flattent args to make sure it can be parsed correctly
+		var flatArgs []any
+		for _, a := range c.args {
+			if s, ok := a.([]any); ok {
+				flatArgs = append(flatArgs, s...)
+			} else {
+				flatArgs = append(flatArgs, a)
+			}
+		}
+
+		err = stmt.QueryRow(flatArgs...).Scan(&c.result)
+
+	}
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

exec/delete.go

@@ -0,0 +1,90 @@
+package exec
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+// Delete represents a delete operation.
+type Delete[T any] struct {
+	target   schema.Table // The table from which records will be deleted.
+	toDelete []T          // A slice of model instances to be deleted.
+}
+
+// NewDelete creates a new instance of Delete.
+//
+// Parameters:
+// - orm: The ORM instance that manages the database connection and schema
+// - toDelete: A slice of model instances to delete
+//
+// Returns:
+// - Delete[T]: A new Delete operation instance
+// - error: An error if the table could not be found in the schema cache
+func NewDelete[T any](orm *simpleorm.ORM, toDelete []T) (Delete[T], error) {
+	table, ok := orm.Cache().Get(reflect.TypeFor[T]().Name())
+	if !ok {
+		return Delete[T]{}, errors.New("Failed to get table from schema cache")
+	}
+
+	return Delete[T]{target: *table, toDelete: toDelete}, nil
+}
+
+// Execute executes the delete operation.
+func (d *Delete[T]) Execute(conn *simpleorm.DBConnection) error {
+	return d.execute(conn, nil)
+}
+
+// execute constructs and executes the DELETE SQL statement.
+//
+// Parameters:
+// - conn: The database connection to use for executing the query
+// - tx: Optional transaction to use instead of a connection
+//
+// Returns:
+// - error: An error if the operation fails
+func (d *Delete[T]) execute(conn *simpleorm.DBConnection, tx *sql.Tx) error {
+	count := len(d.toDelete)
+	dml, err := d.target.GetDeleteDML(count)
+	if err != nil {
+		return err
+	}
+
+	var params []any
+
+	for _, del := range d.toDelete {
+		pkCols, err := getPk(del, d.target)
+		if err != nil {
+			return err
+		}
+
+		for _, pk := range pkCols {
+			params = append(params, pk)
+		}
+	}
+
+	log.LogDebug("%s [%s]", dml, params)
+
+	var stmt *sql.Stmt
+	if tx != nil {
+		stmt, err = tx.Prepare(dml)
+	} else {
+		stmt, err = conn.Prepare(dml)
+	}
+	defer stmt.Close()
+
+	result, err := stmt.Exec(params...)
+	if err != nil {
+		return err
+	} else {
+		rowsAffected, _ := result.RowsAffected()
+		log.LogInfo("Deleted %s row", rowsAffected)
+	}
+
+	return nil
+
+}

exec/exec.go

@@ -0,0 +1,248 @@
+package exec
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+// Created and executes the DDL created by [simpleorm.ORM]
+func ExecuteDDL(conn *simpleorm.DBConnection, orm *simpleorm.ORM) {
+	schema, err := orm.CreateSchema()
+	if err != nil {
+		log.LogError("Failed to run DDL: %s", schema)
+		return
+	}
+
+	log.LogInfo("Executing DDL:\n%s", schema)
+
+	if _, err := conn.Exec(schema); err != nil {
+		log.LogFatalError("%", err)
+	}
+}
+
+// Wraps and represents a DB transaction.
+// Allows for all at once or separate execution of [exec.Exec] implementations.
+type Transaction struct {
+	conn       *simpleorm.DBConnection
+	executions []*Exec[any]
+	tx         *sql.Tx
+	finished   bool
+}
+
+// Creates a new [exec.Transaction].
+// Can be initialized with a set of [exec.Exec]s.
+func NewTransaction(conn *simpleorm.DBConnection, executions ...*Exec[any]) *Transaction {
+	return &Transaction{conn: conn, executions: executions, finished: false}
+}
+
+// The executions assigned to this transaction.
+func (t *Transaction) Executions() []*Exec[any] {
+	return t.executions
+}
+
+// Executes all the [exec.Exec] implementations assigned to this transactions.
+// Begins, commits or rollbacks the transaction.
+// This is a terminal operation, the [exec.Transaction] is considered finished after calling this.
+func (t *Transaction) ExecuteAtOnce() error {
+	if t.finished {
+		return errors.New("Transaction already finished.")
+	}
+
+	if t.tx == nil {
+		tx, err := t.conn.Begin()
+		t.tx = tx
+		if err != nil {
+			t.finished = true
+			return err
+		}
+	}
+
+	for _, exec := range t.executions {
+		err := (*exec).execute(nil, t.tx)
+		if err != nil {
+			rollbackErr := t.Rollback()
+			if rollbackErr != nil {
+				return rollbackErr
+			}
+			return err
+		}
+
+	}
+
+	err := t.tx.Commit()
+	if err != nil {
+		return err
+	}
+
+	t.finished = true
+	return nil
+}
+
+// Executes and assigns the passed [exec.Exec]s to the Transaction.
+// Calls rollback in case of an error.
+// This is NOT a terminal operation, transactions still has to be committed.
+func (t *Transaction) Execute(execs ...Exec[any]) error {
+	if t.finished {
+		return errors.New("Transaction already finished.")
+	}
+
+	for _, exec := range execs {
+		execPtr := &exec
+		t.executions = append(t.executions, execPtr)
+		if t.tx == nil {
+			tx, err := t.conn.Begin()
+			t.tx = tx
+			if err != nil {
+				t.finished = true
+				return err
+			}
+		}
+
+		err := (*execPtr).execute(nil, t.tx)
+		if err != nil {
+			rollbackErr := t.Rollback()
+			if rollbackErr != nil {
+				return rollbackErr
+			}
+			return err
+		}
+
+	}
+
+	return nil
+}
+
+// Finishes the transaction, commits the changes.
+// This is terminal operation.
+func (t *Transaction) Finish() error {
+	if t.finished {
+		return errors.New("Transaction already finished.")
+	}
+
+	if t.tx == nil {
+		return errors.New("Transaction is nil.")
+	}
+
+	t.tx.Commit()
+	t.finished = true
+	return nil
+}
+
+// Rollbacks and aborts the transaction.
+// This is a terminal operation.
+func (t *Transaction) Rollback() error {
+	if t.finished {
+		return errors.New("Transaction already finished.")
+	}
+
+	if t.tx == nil {
+		return errors.New("Transaction is nil.")
+	}
+
+	rollbackErr := t.tx.Rollback()
+	if rollbackErr != nil {
+		return rollbackErr
+	}
+	t.finished = true
+	return nil
+}
+
+type Exec[T any] interface {
+	Execute(conn *simpleorm.DBConnection) error
+	execute(conn *simpleorm.DBConnection, tx *sql.Tx) error
+}
+
+func createSelectResultContainer(t schema.Table) []any {
+	typ := t.Type()
+	vals := make([]any, typ.NumField())
+	for i := range vals {
+		switch typ.Field(i).Type.Kind().String() {
+		case "string":
+			var fieldContainer string
+			vals[i] = &fieldContainer
+		case "int", "bool":
+			var fieldContainer int
+			vals[i] = &fieldContainer
+		case "int64", "time.Time":
+			var fieldContainer int64
+			vals[i] = &fieldContainer
+		}
+	}
+	return vals
+}
+
+func prepareParams(src any, t schema.Table) []any {
+	typ := t.Type()
+	var params []any
+	for _, col := range t.Columns() {
+		_, ok := col.Modifiers["pk"]
+		if ok && t.IsPkAuto() {
+			continue
+		}
+		field, ok := typ.FieldByName(col.FieldName)
+		if !ok {
+			continue
+		}
+		fieldValue := reflect.ValueOf(src).FieldByIndex(field.Index)
+
+		params = append(params, col.Encode(fieldValue))
+	}
+	return params
+}
+
+func getPk(src any, t schema.Table) ([]any, error) {
+	typ := t.Type()
+	var values []any
+	for _, constraint := range t.Constraints() {
+		if constraint.Type == "pk" {
+			for _, col := range constraint.Columns {
+				field, ok := typ.FieldByName(col.FieldName)
+				if !ok {
+					continue
+
+				}
+				fieldValue := reflect.ValueOf(src).FieldByIndex(field.Index)
+				values = append(values, fieldValue.Interface())
+			}
+		}
+	}
+	if len(values) == 0 {
+		return nil, errors.New("Could not determine pk column!")
+	}
+
+	return values, nil
+}
+
+func readRows[T any](table schema.Table, rows *sql.Rows) ([]T, error) {
+	rowContainer := createSelectResultContainer(table)
+
+	var results []T
+
+	for rows.Next() {
+		err := rows.Scan(rowContainer...)
+		if err != nil {
+			return nil, err
+		}
+
+		targetType := table.Type()
+		cols := table.Columns()
+		parsedResult := reflect.New(targetType)
+		for i, fieldVal := range rowContainer {
+			col := cols[i]
+			targetField := parsedResult.Elem().Field(i)
+
+			rawValue := reflect.Indirect(reflect.ValueOf(fieldVal))
+			decoded := reflect.ValueOf(col.Decode(targetField.Type().Name(), rawValue))
+
+			targetField.Set(decoded)
+		}
+		parsedObj := reflect.Indirect(parsedResult).Interface().(T)
+		results = append(results, parsedObj)
+	}
+	return results, nil
+}

exec/insert.go

@@ -0,0 +1,122 @@
+package exec
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+// Insert represents an insert query operation.
+type Insert[T any] struct {
+	target   schema.Table
+	toInsert []T
+	results  []T
+}
+
+// Creates a new insert operation for the given model type.
+//
+// Parameters:
+// - orm: The ORM instance that manages the database connection and schema
+// - toInsert: A variadic list of model instances to insert
+//
+// Returns:
+// - Insert[T]: A new insert operation instance
+// - error: An error if the table could not be found in the schema cache
+
+func NewInsert[T any](orm *simpleorm.ORM, toInsert ...T) (Insert[T], error) {
+	table, ok := orm.Cache().Get(reflect.TypeFor[T]().Name())
+	if !ok {
+		return Insert[T]{}, errors.New("Failed to get table from schema cache")
+	}
+
+	return Insert[T]{target: *table, toInsert: toInsert}, nil
+}
+
+// Returns the results of the insert operation.
+//
+// Returns:
+// - []T: A slice of model instances representing the inserted rows
+
+func (ins *Insert[T]) Results() []T {
+	return ins.results
+}
+
+// Executes the insert operation using the provided database connection.
+//
+// Parameters:
+// - conn: The database connection to use for executing the query
+//
+// Returns:
+// - error: An error if the operation fails
+func (ins *Insert[T]) Execute(conn *simpleorm.DBConnection) error {
+
+	return ins.execute(conn, nil)
+}
+
+// Executes the insert operation using the provided database connection or transaction.
+//
+// Parameters:
+// - conn: The database connection to use for executing the query
+// - tx: Optional transaction to use instead of a connection
+//
+// Returns:
+// - error: An error if the operation fails
+//
+// Implementation Details:
+// 1. Constructs the SQL INSERT statement using GetInsertDML
+// 2. Prepares parameters by flattening nested any values
+// 3. Executes the statement and maps results to model instances
+func (ins *Insert[T]) execute(conn *simpleorm.DBConnection, tx *sql.Tx) error {
+	dml, err := ins.target.GetInsertDML(len(ins.toInsert))
+	if err != nil {
+		return err
+	}
+
+	var params []any
+	for i := range len(ins.toInsert) {
+		actualParams := prepareParams(ins.toInsert[i], ins.target)
+		if len(params) == 0 {
+			params = make([]any, len(ins.toInsert)*len(actualParams))
+		}
+		for j := range actualParams {
+			params[(i*len(actualParams))+j] = actualParams[j]
+		}
+	}
+
+	log.LogDebug("%s [%s]", dml, params)
+
+	var stmt *sql.Stmt
+	if tx != nil {
+		stmt, err = tx.Prepare(dml)
+	} else {
+		stmt, err = conn.Prepare(dml)
+	}
+	defer stmt.Close()
+
+	// Flattent args to make sure it can be parsed correctly
+	var flatParams []any
+	for _, param := range params {
+		if s, ok := param.([]any); ok {
+			flatParams = append(flatParams, s...)
+		} else {
+			flatParams = append(flatParams, param)
+		}
+	}
+
+	rows, err := stmt.Query(flatParams...)
+
+	if err != nil {
+		return err
+	}
+
+	ins.results, err = readRows[T](ins.target, rows)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

exec/select.go

@@ -0,0 +1,153 @@
+package exec
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+// Select execution which is translated to a select sql query.
+type Select[T any] struct {
+	target    schema.Table
+	whereStmt string
+	args      []any
+	limit     int64
+	offset    int64
+	ordering  []schema.OrderBy
+	results   []T
+}
+
+// Creates the select query builder
+func NewSelect[T any](orm *simpleorm.ORM) (Select[T], error) {
+	table, ok := orm.Cache().Get(reflect.TypeFor[T]().Name())
+	if !ok {
+		return Select[T]{}, errors.New("Failed to get table from schema cache")
+	}
+
+	return Select[T]{target: *table, limit: -1, offset: -1}, nil
+}
+
+// Sets the where part of the select query and the arguments
+// Returns the pointer of the Select instance
+func (s *Select[T]) Where(whereStmt string, args ...any) *Select[T] {
+	s.whereStmt = whereStmt
+	s.args = args
+	return s
+}
+
+// Sets the limit part of the select query
+// Returns the pointer of the Select instance
+func (s *Select[T]) Limit(limit int64) *Select[T] {
+	s.limit = limit
+	return s
+}
+
+// Sets the offset part of the select query
+// Returns the pointer of the Select instance
+func (s *Select[T]) Offset(offset int64) *Select[T] {
+	s.offset = offset
+	return s
+}
+
+// Sets the order by part of the select query
+// Returns the pointer of the Select instance
+func (s *Select[T]) OrderBy(ordering ...schema.OrderBy) *Select[T] {
+	s.ordering = ordering
+	return s
+}
+
+// Returns the result of the select
+func (s *Select[T]) Results() []T {
+	return s.results
+}
+
+// Executes the select query based on the Select exec instance
+// Returns an error if theres any
+func (s *Select[T]) Execute(conn *simpleorm.DBConnection) error {
+	return s.execute(conn, nil)
+}
+
+// Executes the select query based on the Select exec instance
+// If tx is given, the transaction is used instead of the conn
+// Returns an error if theres any
+func (s *Select[T]) execute(conn *simpleorm.DBConnection, tx *sql.Tx) error {
+	// Reinit the results, new execution
+	s.results = []T{}
+	dml, err := s.target.GetSelectDML()
+	if err != nil {
+		return err
+	}
+
+	if s.whereStmt != "" {
+		dml += " WHERE " + s.whereStmt
+	}
+
+	if len(s.ordering) > 0 {
+		orderBy, err := s.target.GetOrderByDML(s.ordering...)
+		if err != nil {
+			log.LogError("Failed to create ORDER BY part: %s", err)
+		} else {
+			dml += orderBy
+		}
+	}
+
+	var effectiveArgs []any = s.args
+	if s.limit != -1 {
+		dml += " LIMIT ?"
+		effectiveArgs = append(effectiveArgs, s.limit)
+	}
+
+	if s.offset != -1 {
+		dml += " OFFSET ?"
+		effectiveArgs = append(effectiveArgs, s.offset)
+	}
+
+	log.LogInfo("Preparing sql: %s", dml)
+	log.LogDebug("Preparing sql: %s, with args: %s", dml, effectiveArgs)
+
+	var stmt *sql.Stmt
+	if tx != nil {
+		stmt, err = tx.Prepare(dml)
+	} else {
+		stmt, err = conn.Prepare(dml)
+	}
+
+	if err != nil {
+		return err
+	}
+	defer stmt.Close()
+
+	log.LogDebug("Executing statement: %s", stmt)
+
+	var rows *sql.Rows
+	if len(effectiveArgs) == 0 {
+		rows, err = stmt.Query()
+	} else {
+		// Flattent args to make sure it can be parsed correctly
+		var flatArgs []any
+		for _, a := range effectiveArgs {
+			if s, ok := a.([]any); ok {
+				flatArgs = append(flatArgs, s...)
+			} else {
+				flatArgs = append(flatArgs, a)
+			}
+		}
+		rows, err = stmt.Query(flatArgs...)
+
+	}
+
+	if err != nil {
+		return err
+	}
+
+	s.results, err = readRows[T](s.target, rows)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

exec/update.go

@@ -0,0 +1,85 @@
+package exec
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+// Update represents an update operation.
+type Update[T any] struct {
+	target   schema.Table // The table where records will be updated.
+	toUpdate T            // A model instance with the new values.
+}
+
+// NewUpdate creates a new instance of Update.
+//
+// Parameters:
+// - orm: The ORM instance that manages the database connection and schema
+// - toUpdate: A model instance with new values
+//
+// Returns:
+// - Update[T]: A new Update operation instance
+// - error: An error if the table could not be found in the schema cache
+func NewUpdate[T any](orm *simpleorm.ORM, toUpdate T) (Update[T], error) {
+	table, ok := orm.Cache().Get(reflect.TypeFor[T]().Name())
+	if !ok {
+		return Update[T]{}, errors.New("Failed to get table from schema cache")
+	}
+
+	return Update[T]{target: *table, toUpdate: toUpdate}, nil
+}
+
+// Execute executes the update operation.
+func (u Update[T]) Execute(conn *simpleorm.DBConnection) error {
+	return u.execute(conn, nil)
+}
+
+// execute constructs and executes the UPDATE SQL statement.
+//
+// Parameters:
+// - conn: The database connection to use for executing the query
+// - tx: Optional transaction to use instead of a connection
+//
+// Returns:
+// - error: An error if the operation fails
+func (u Update[T]) execute(conn *simpleorm.DBConnection, tx *sql.Tx) error {
+	dml, err := u.target.GetUpdateDML()
+	if err != nil {
+		return err
+	}
+
+	params := prepareParams(u.toUpdate, u.target)
+
+	pkCols, err := getPk(u.toUpdate, u.target)
+	if err != nil {
+		return err
+	}
+	// Put the pks back at the end
+	for _, pk := range pkCols {
+		params = append(params, pk)
+	}
+
+	log.LogDebug("%s [%s]", dml, params)
+
+	var stmt *sql.Stmt
+	if tx != nil {
+		stmt, err = tx.Prepare(dml)
+	} else {
+		stmt, err = conn.Prepare(dml)
+	}
+	defer stmt.Close()
+
+	result, err := stmt.Exec(params...)
+	if err != nil {
+		return err
+	} else {
+		rowsAffected, _ := result.RowsAffected()
+		log.LogInfo("Updated %s row", rowsAffected)
+	}
+	return nil
+}

main_test.go

@@ -1,45 +0,0 @@
-package simpleorm_test
-
-import (
-	"os"
-	"testing"
-
-	_ "github.com/mattn/go-sqlite3"
-	log "gitlab.com/gdulai/simpleloglvl"
-)
-
-type Test struct {
-	ID          int    `sql:"pk"`
-	Int64Field  int64  `sql:"nn"`
-	IntField    int    `sql:"nn"`
-	StringField string `sql:"nn"`
-}
-
-type TestWithFk struct {
-	ID     int `sql:"pk"`
-	TestID int `sql:"nn;fk=Test.ID"`
-}
-
-type TestWithFkAndFkId struct {
-	ID     int `sql:"pk"`
-	TestID int `sql:"nn;fk=Test.ID;fk_id=custom_fk"`
-}
-
-type TestWithCompositePk struct {
-	ID   int    `sql:"nn;pk"`
-	Name string `sql:"nn;pk"`
-}
-
-type TestWithCompositeFk struct {
-	ID              int    `sql:"nn;pk"`
-	CompositeFkId   int    `sql:"nn;fk=TestWithCompositePk.ID;"`
-	CompositeFkName string `sql:"nn;fk=TestWithCompositePk.Name;"`
-}
-
-func TestMain(m *testing.M) {
-	log.SetupLogs("Info")
-
-	code := m.Run()
-
-	os.Exit(code)
-}

orm.go

@@ -6,45 +6,60 @@ import (
 	"reflect"
 	"strings"
 
+	"git.gdulai.com/gdulai/simpleorm/cache"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+
 	log "gitlab.com/gdulai/simpleloglvl"
 )
 
 // Type to access the ORM functionalities in a structured manner-
 type ORM struct {
-	cache *OrmCache
+	cache *cache.SchemaCache
 }
 
-// Inits the ORM library.
-// Param objs is an array which should be an array of the types which describe the tables.
+// NewOrm inits and creates an instance ORM library.
+//
+// obj is an array which should be an array of the types which describe the tables.
 func NewORM(objs ...any) *ORM {
-	var parsers []*Parser
-	var tables []*Table
+	typeParsers := make(map[string]*schema.Parser)
+
+	log.LogDebug("[ORM] Parsing entities to tables...")
+	log.LogDebug("[ORM] Step 1: Parsing table columns")
 	for _, obj := range objs {
-		log.LogDebug("[ORM] Mapping type for: %s", reflect.TypeOf(obj).Name())
-		parser := NewParser(obj)
-		parsers = append(parsers, parser)
-		tables = append(tables, parser.ParseColumns())
+		typ := reflect.TypeOf(obj)
+		log.LogDebug("[ORM] Mapping type for: %s", typ.Name())
+
+		parser := schema.NewParser(obj)
+		parser.ParseColumns()
+
+		typeParsers[typ.Name()] = parser
 	}
 
-	log.LogDebug("[ORM] Tables initiated, creating cache.")
+	log.LogDebug("[ORM] Step 1: Finished parsing columns!")
+	log.LogDebug("[ORM] Step 2: Parsing constraints...")
+
+	for _, parser := range typeParsers {
+		parser.ParseConstraints(typeParsers)
+	}
+
+	log.LogDebug("[ORM] Step 2: Finished parsing contraints!")
+	log.LogDebug("[ORM] Step 3: Creating and caching schema...")
+
+	var tables []*schema.Table
+	for _, parser := range typeParsers {
+		tables = append(tables, parser.ParseTable())
+	}
 
 	// Create cache with the initialized tables
-	cache := NewOrmCache(tables)
+	cache := cache.NewSchemaCache(tables)
 
-	log.LogDebug("[ORM] Cache created.")
-
-	// Finish the parsing with the constraints and add the to the tables
-	for _, parser := range parsers {
-		log.LogDebug("[ORM] Parsing constraing for: %s", parser.Table.Name)
-		parser.ParseConstraints(cache)
-		log.LogDebug("[ORM] Parsed constraints for: %s", parser.Table.Name)
-	}
+	log.LogDebug("[ORM] Step 3: Cache created.")
 
 	return &ORM{cache: cache}
 }
 
-// Builds the DDL and returns it as a string
-func (orm ORM) CreateDDL() string {
+// CreateSchmea builds the DDL and returns it as a string
+func (orm *ORM) CreateSchema() (string, error) {
 	var ddl strings.Builder
 
 	tables := orm.cache.GetAll()
@@ -53,8 +68,15 @@ func (orm ORM) CreateDDL() string {
 		if i != 0 {
 			ddl.WriteString("\n")
 		}
-		ddl.WriteString(table.ToDDL())
+		tableDdl, err := table.GetDDL()
+		if err != nil {
+			return "", err
+		}
+		ddl.WriteString(tableDdl)
 	}
+	return ddl.String(), nil
+}
 
-	return ddl.String()
+func (orm *ORM) Cache() *cache.SchemaCache {
+	return orm.cache
 }

ormexec.go

@@ -1,191 +0,0 @@
-package simpleorm
-
-import (
-	"database/sql"
-	"errors"
-	"reflect"
-
-	log "gitlab.com/gdulai/simpleloglvl"
-)
-
-type ORMExec[T any] struct {
-	orm  *ORM
-	conn *DBConnection
-}
-
-func CreateExecution[T any](orm *ORM, conn *DBConnection) ORMExec[T] {
-	return ORMExec[T]{orm: orm, conn: conn}
-}
-
-func InitDB(conn *DBConnection, orm *ORM) {
-	// Force a real DB interaction
-	if _, err := conn.db.Exec(orm.CreateDDL()); err != nil {
-		log.LogFatalError("%", err)
-	}
-}
-
-func (ormExec ORMExec[T]) Select(desc T, whereStmt string, args ...any) ([]T, error) {
-	lookup := reflect.TypeOf(desc).Name()
-	table, ok := ormExec.orm.cache.Get(lookup)
-	if !ok {
-		return []T{}, errors.New("Failed to get descriptor from cache! " + lookup)
-	}
-	sqlStr := table.ToSelectDML()
-	if whereStmt != "" {
-		sqlStr += " WHERE " + whereStmt
-	}
-	log.LogDebug("Preparing sql: %s, with args: %s", sqlStr, args)
-
-	stmt, err := ormExec.conn.db.Prepare(sqlStr)
-	if err != nil {
-		return nil, err
-	}
-	defer stmt.Close()
-
-	log.LogDebug("Executing statement: %s", stmt)
-
-	var rows *sql.Rows
-	if len(args) == 0 {
-		rows, err = stmt.Query()
-	} else {
-		// Flattent args to make sure it can be parsed correctly
-		var flatArgs []any
-		for _, a := range args {
-			if s, ok := a.([]any); ok {
-				flatArgs = append(flatArgs, s...)
-			} else {
-				flatArgs = append(flatArgs, a)
-			}
-		}
-		rows, err = stmt.Query(flatArgs...)
-
-	}
-
-	if err != nil {
-		return nil, err
-	}
-
-	rowContainer := table.createSelectResultContainer()
-
-	var results []T
-
-	for rows.Next() {
-		err = rows.Scan(rowContainer...)
-		if err != nil {
-			return nil, err
-		}
-
-		targetType := table.Type
-		parsedResult := reflect.New(targetType)
-		for i, fieldVal := range rowContainer {
-			parsedResult.Elem().Field(i).Set(reflect.Indirect(reflect.ValueOf(fieldVal)))
-		}
-		parsedObj := reflect.Indirect(parsedResult).Interface().(T)
-		results = append(results, parsedObj)
-	}
-
-	return results, nil
-}
-
-func (ormExec ORMExec[T]) Insert(src ...T) error {
-	typeName := reflect.TypeOf(src[0]).Name()
-	table, ok := ormExec.orm.cache.Get(typeName)
-	if !ok {
-		return errors.New("Could not find table for type " + typeName)
-	}
-
-	sql := table.ToInsertDML(len(src))
-	var params []any
-	for i := range len(src) {
-		actualParams := table.prepareParams(src[i])
-		if len(params) == 0 {
-			params = make([]any, len(src)*len(actualParams))
-		}
-		for j := range actualParams {
-			params[(i*len(actualParams))+j] = actualParams[j]
-		}
-	}
-
-	log.LogInfo("%s [%s]", sql, params)
-
-	stmt, err := ormExec.conn.db.Prepare(sql)
-	if err != nil {
-		return err
-	}
-	defer stmt.Close()
-
-	result, err := stmt.Exec(params...)
-	if err != nil {
-		return err
-	} else {
-		rowsAffected, _ := result.RowsAffected()
-		log.LogInfo("Inserted %s row", rowsAffected)
-	}
-	return nil
-}
-
-func (ormExec ORMExec[T]) Update(src T) error {
-	typeName := reflect.TypeOf(src).Name()
-	table, ok := ormExec.orm.cache.Get(reflect.TypeOf(src).Name())
-	if !ok {
-		return errors.New("Could not find table for type " + typeName)
-	}
-
-	sql := table.ToUpdateDML(src)
-	params := table.prepareParams(src)
-
-	pk, err := table.getPk(src)
-	if err != nil {
-		return err
-	}
-	// Put the pk back at the end
-	params = append(params, pk)
-
-	log.LogInfo("%s [%s]", sql, params)
-
-	stmt, err := ormExec.conn.db.Prepare(sql)
-	if err != nil {
-		return err
-	}
-	defer stmt.Close()
-
-	result, err := stmt.Exec(params...)
-	if err != nil {
-		return err
-	} else {
-		rowsAffected, _ := result.RowsAffected()
-		log.LogInfo("Updated %s row", rowsAffected)
-	}
-	return nil
-}
-
-func (ormExec ORMExec[T]) Delete(src T) error {
-	typeName := reflect.TypeOf(src).Name()
-	table, ok := ormExec.orm.cache.Get(reflect.TypeOf(src).Name())
-	if !ok {
-		return errors.New("Could not find table for type " + typeName)
-	}
-
-	sql := table.ToDeleteDML(src)
-	pk, err := table.getPk(src)
-	if err != nil {
-		return err
-	}
-
-	log.LogInfo("%s [%s]", sql, pk)
-
-	stmt, err := ormExec.conn.db.Prepare(sql)
-	if err != nil {
-		return err
-	}
-	defer stmt.Close()
-
-	result, err := stmt.Exec(pk)
-	if err != nil {
-		return err
-	} else {
-		rowsAffected, _ := result.RowsAffected()
-		log.LogInfo("Deleted %s row", rowsAffected)
-	}
-	return nil
-}

ormexec_test.go

@@ -1,114 +0,0 @@
-package simpleorm_test
-
-import (
-	"os"
-	"simpleorm"
-	"testing"
-
-	log "gitlab.com/gdulai/simpleloglvl"
-)
-
-func TestSelectEmpty(t *testing.T) {
-	// GIVEN
-	conn := simpleorm.OpenConnection("sqlite3", "file:test.db")
-	defer cleanUp("test.db", conn)
-
-	orm := simpleorm.NewORM(Test{}, TestWithFk{}, TestWithFkAndFkId{},
-		TestWithCompositePk{}, TestWithCompositeFk{})
-
-	simpleorm.InitDB(conn, orm)
-
-	exec := simpleorm.CreateExecution[Test](orm, conn)
-	// WHEN
-	res, err := exec.Select(Test{}, "")
-	// THEN
-	if err != nil {
-		log.LogError("Select failure. %s", err)
-		t.Fail()
-	}
-	if len(res) > 0 {
-		log.LogError("Expected empty result.")
-		t.Fail()
-	}
-}
-
-func TestInsertAndSelectSingle(t *testing.T) {
-	// GIVEN
-	conn := simpleorm.OpenConnection("sqlite3", "file:test.db")
-	defer cleanUp("test.db", conn)
-
-	orm := simpleorm.NewORM(Test{}, TestWithFk{}, TestWithFkAndFkId{},
-		TestWithCompositePk{}, TestWithCompositeFk{})
-
-	simpleorm.InitDB(conn, orm)
-
-	exec := simpleorm.CreateExecution[Test](orm, conn)
-
-	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
-	err := exec.Insert(testObj)
-	if err != nil {
-		log.LogError("Insert failure. %s", err)
-		t.Fail()
-	}
-	// WHEN
-	res, err := exec.Select(Test{}, "")
-	// THEN
-	if err != nil {
-		log.LogError("Select failure. %s", err)
-		t.Fail()
-	}
-	if len(res) != 1 {
-		log.LogError("Selec test failed. Expected: 1, Actual: %s", len(res))
-		t.Fail()
-	}
-
-	singleRes := res[0]
-	if singleRes.ID != 1 || singleRes.Int64Field != 54 || singleRes.IntField != 12 || singleRes.StringField != "asdf" {
-		log.LogError("Invalid result. Expected: %s, Actual: %s", testObj, singleRes)
-		t.Fail()
-	}
-
-}
-
-func TestInsertMultipleAndSelectWithParam(t *testing.T) {
-	// GIVEN
-	conn := simpleorm.OpenConnection("sqlite3", "file:test.db")
-	defer cleanUp("test.db", conn)
-
-	orm := simpleorm.NewORM(Test{}, TestWithFk{}, TestWithFkAndFkId{},
-		TestWithCompositePk{}, TestWithCompositeFk{})
-
-	simpleorm.InitDB(conn, orm)
-
-	exec := simpleorm.CreateExecution[Test](orm, conn)
-
-	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
-	testObjSecond := Test{Int64Field: 12, IntField: 54, StringField: "fdsa"}
-	err := exec.Insert(testObj, testObjSecond)
-	if err != nil {
-		log.LogError("Insert failure. %s", err)
-		t.Fail()
-	}
-	// WHEN
-	res, err := exec.Select(Test{}, "string_field = ?", "fdsa")
-	// THEN
-	if err != nil {
-		log.LogError("Select failure. %s", err)
-		t.Fail()
-	}
-	if len(res) != 1 {
-		log.LogError("Select test failed. Expected: 1, Actual: %s", len(res))
-		t.Fail()
-	}
-
-	singleRes := res[0]
-	if singleRes.ID != 2 || singleRes.Int64Field != 12 || singleRes.IntField != 54 || singleRes.StringField != "fdsa" {
-		log.LogError("Invalid result. Expected: %s, Actual: %s", testObjSecond, singleRes)
-		t.Fail()
-	}
-}
-
-func cleanUp(dbFile string, conn *simpleorm.DBConnection) {
-	conn.Close()
-	os.Remove(dbFile)
-}

parser.go

@@ -1,114 +0,0 @@
-package simpleorm
-
-import (
-	"reflect"
-	"strings"
-	"unicode"
-
-	log "gitlab.com/gdulai/simpleloglvl"
-)
-
-type Parser struct {
-	typ   reflect.Type
-	Table *Table
-}
-
-func NewParser[T any](obj T) *Parser {
-	objType := reflect.TypeOf(obj)
-	return &Parser{typ: objType}
-}
-
-// This is step 1 of the parsing, it creates the table instance and
-func (p *Parser) ParseColumns() *Table {
-	table := Table{Name: camelToSnake(p.typ.Name()), Type: p.typ}
-
-	var columns []Column
-	for field := range p.typ.Fields() {
-		field := field
-		col := NewColumn(camelToSnake((field.Name)), field.Name, determineType(field.Type), field.Tag)
-		columns = append(columns, col)
-	}
-
-	table.Columns = columns
-	p.Table = &table
-	return p.Table
-}
-
-func (p *Parser) ParseConstraints(cache *OrmCache) {
-	pkConstraint := Constraint{Name: "pk_" + strings.ToLower(p.Table.Name), Type: "pk"}
-	fkConstraints := make(map[string]Constraint)
-	for _, col := range p.Table.Columns {
-		_, ok := col.Modifiers["pk"]
-		if ok {
-			pkConstraint.Columns = append(pkConstraint.Columns, col)
-			continue
-		}
-
-		fkMod, ok := col.Modifiers["fk"]
-		if !ok {
-			continue
-		}
-
-		fkModParts := strings.Split(fkMod, ".")
-		refTable, ok := cache.Get(fkModParts[0])
-		if !ok {
-			log.LogError("[ORM] Table %s not found in OrmCache!", fkModParts[0])
-			return
-		}
-
-		fkId, ok := col.Modifiers["fk_id"]
-		if fkId == "" {
-			fkId = "fk_" + strings.ToLower(refTable.Name)
-		}
-
-		fkConstraint, ok := fkConstraints[fkId]
-		if !ok {
-			fkConstraint = Constraint{Name: fkId, Type: "fk", RefTable: refTable}
-		}
-
-		fkConstraint.Columns = append(fkConstraint.Columns, col)
-
-		refField := fkModParts[1]
-		for _, refC := range refTable.Columns {
-			if refC.FieldName == refField {
-				fkConstraint.RefColumns = append(fkConstraint.RefColumns, refC)
-			}
-		}
-
-		fkConstraints[fkId] = fkConstraint
-	}
-	p.Table.Constraints = append(p.Table.Constraints, pkConstraint)
-	for _, fkConstraint := range fkConstraints {
-		p.Table.Constraints = append(p.Table.Constraints, fkConstraint)
-	}
-
-}
-
-func determineType(typ reflect.Type) string {
-	typStr := typ.String()
-	switch typStr {
-	case "string":
-		return "TEXT"
-	case "int":
-		return "INTEGER"
-	case "time.Time", "int64":
-		return "BIGINT"
-	}
-
-	return "VARCHAR(255)"
-}
-
-func camelToSnake(str string) string {
-	var snake strings.Builder
-	isPrevUpper := true
-	for _, c := range str {
-		if unicode.IsUpper(c) && !isPrevUpper {
-			snake.WriteString("_" + string(unicode.ToUpper(c)))
-			isPrevUpper = true
-		} else {
-			snake.WriteString(string(unicode.ToUpper(c)))
-			isPrevUpper = unicode.IsUpper(c)
-		}
-	}
-	return snake.String()
-}

repository/repository.go

@@ -0,0 +1,134 @@
+package repository
+
+import (
+	"reflect"
+	"strings"
+
+	"git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/exec"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+type HasPK interface {
+	IsInsertable() bool
+}
+
+type Repository[T HasPK] struct {
+	conn *simpleorm.DBConnection
+	orm  *simpleorm.ORM
+}
+
+func NewRepository[T HasPK](conn *simpleorm.DBConnection, orm *simpleorm.ORM) *Repository[T] {
+	return &Repository[T]{conn: conn, orm: orm}
+}
+
+func (r *Repository[T]) SelectAll() []*T {
+	selectExec, err := exec.NewSelect[T](r.orm)
+	if err != nil {
+		log.LogError("Failed to create select execution: %s", err)
+		return []*T{}
+	}
+
+	err = selectExec.Execute(r.conn)
+	if err != nil {
+		log.LogError("Failed to load projects: %s", err)
+		return []*T{}
+	}
+
+	selectRes := selectExec.Results()
+	res := make([]*T, 0, len(selectRes))
+	for i := range selectRes {
+		res = append(res, &selectRes[i])
+	}
+
+	return res
+}
+
+func (r *Repository[T]) SelectByPk(pks ...any) *T {
+	table, ok := r.orm.Cache().Get(reflect.TypeFor[T]().Name())
+	if !ok {
+		log.LogError("Could not get cached Table!")
+		return nil
+	}
+
+	var whereStmtBuilder strings.Builder
+
+	for _, constr := range table.Constraints() {
+		if constr.Type != "pk" {
+			continue
+		}
+
+		for i, col := range constr.Columns {
+			if i != 0 {
+				whereStmtBuilder.WriteString(" AND ")
+			}
+
+			whereStmtBuilder.WriteString(col.Name + " = ?")
+		}
+
+	}
+
+	selectExec, err := exec.NewSelect[T](r.orm)
+	if err != nil {
+		log.LogError("Failed to create select execution: %s", err)
+		return nil
+	}
+
+	selectExec.Where(whereStmtBuilder.String(), pks)
+
+	err = selectExec.Execute(r.conn)
+	if err != nil {
+		log.LogError("Failed to load entity: %s", err)
+		return nil
+	}
+	selectRes := selectExec.Results()
+	if len(selectRes) != 1 {
+		log.LogError("Invalid result number of results: %s", len(selectRes))
+		return nil
+	}
+
+	return &selectRes[0]
+}
+
+func (r *Repository[T]) Save(entity *T) error {
+	// Insert
+	if (*entity).IsInsertable() {
+		insertExec, err := exec.NewInsert[T](r.orm, *entity)
+		if err != nil {
+			return err
+		}
+		err = insertExec.Execute(r.conn)
+		if err != nil {
+			return err
+		}
+		result := insertExec.Results()
+		// Point to the new inserted result
+		*entity = result[0]
+		return nil
+	}
+
+	updateExec, err := exec.NewUpdate[T](r.orm, *entity)
+	if err != nil {
+		return err
+	}
+
+	err = updateExec.Execute(r.conn)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (r *Repository[T]) Delete(entity *T) {
+	deleteExec, err := exec.NewDelete[T](r.orm, []T{*entity})
+	if err != nil {
+		log.LogError("Failed to create delete execution: %s", err)
+		return
+	}
+	err = deleteExec.Execute(r.conn)
+	if err != nil {
+		log.LogError("Delete failed: %s", err)
+		return
+	}
+}

schema/column.go

@@ -0,0 +1,129 @@
+package schema
+
+import (
+	"errors"
+	"reflect"
+	"strings"
+	"time"
+)
+
+type Column struct {
+	Name      string
+	FieldName string
+	Type      string
+	Modifiers map[string]string
+}
+
+func NewColumn(name string, typ string, fieldName string, tag reflect.StructTag) Column {
+	return Column{name, typ, fieldName, determineModifiers(tag)}
+}
+
+func determineModifiers(tag reflect.StructTag) map[string]string {
+	modifiers := make(map[string]string)
+	sqlTag := tag.Get("sql")
+	if sqlTag == "" {
+		return modifiers
+	}
+
+	rawModifiers := strings.SplitSeq(sqlTag, ";")
+	for rawModifier := range rawModifiers {
+		if strings.Contains(rawModifier, "=") {
+			keyValue := strings.Split(rawModifier, "=")
+			modifiers[keyValue[0]] = keyValue[1]
+		} else {
+			modifiers[rawModifier] = ""
+		}
+	}
+	return modifiers
+}
+
+func (c *Column) GetDDL() (string, error) {
+	var ddlBuilder strings.Builder
+
+	ddlBuilder.WriteString(c.Name)
+	ddlBuilder.WriteString(" ")
+	ddlBuilder.WriteString(c.Type)
+
+	inlineMods := c.inlineModifiers()
+	for _, mod := range inlineMods {
+		ddlBuilder.WriteString(" ")
+		ddlBuilder.WriteString(mod)
+	}
+
+	return ddlBuilder.String(), nil
+}
+
+func (c *Column) inlineModifiers() []string {
+	var mods []string
+	for k := range c.Modifiers {
+		switch k {
+		case "nn":
+			mods = append(mods, "NOT NULL")
+		}
+	}
+	return mods
+}
+
+func (c Column) GetSelectDML() (string, error) {
+	return c.Name, nil
+}
+
+func (c Column) GetInsertDML() (string, error) {
+	return c.Name, nil
+}
+
+func (c Column) GetUpdateDML() (string, error) {
+	return c.Name + " = ?", nil
+}
+
+func (Column) GetDeleteDML() (string, error) {
+	return "", errors.New("No delete DML for columns")
+}
+
+func (c *Column) IsPK() bool {
+	_, ok := c.Modifiers["pk"]
+	return ok
+}
+
+// Encodes the value to be DB compatible
+func (c Column) Encode(value reflect.Value) any {
+	typ := value.Type().String()
+
+	var encoded any
+	switch typ {
+	case "time.Time":
+		timeVal := value.Interface().(time.Time)
+		encoded = timeVal.UnixMilli()
+	case "bool":
+		boolVal := value.Interface().(bool)
+		if boolVal {
+			encoded = 1
+		} else {
+			encoded = false
+		}
+	default:
+		encoded = value.Interface()
+	}
+
+	return encoded
+}
+
+// Decodes the raw value from the DBs
+func (c Column) Decode(expected string, rawValue reflect.Value) any {
+	var decoded any
+	switch expected {
+	case "time.Time":
+		decoded = time.UnixMilli(rawValue.Interface().(int64))
+	case "bool":
+		rawValue := rawValue.Interface().(int)
+		if rawValue > 0 {
+			decoded = true
+		} else {
+			decoded = false
+		}
+	default:
+		decoded = rawValue.Interface()
+	}
+
+	return decoded
+}

schema/constraint.go

@@ -0,0 +1,87 @@
+package schema
+
+import (
+	"errors"
+	"strings"
+
+	"git.gdulai.com/gdulai/simpleorm/util"
+)
+
+type Constraint struct {
+	Name        string
+	Type        string
+	Columns     []Column
+	RefTypeName string
+	RefColumns  []Column
+}
+
+func (c *Constraint) GetDDL() (string, error) {
+	switch c.Type {
+	case "pk":
+		return c.getPkDDL(), nil
+	case "fk":
+		return c.getFkDDL(), nil
+	}
+
+	return "", errors.New("Unimplemented constraing: " + c.Type)
+}
+
+func (c *Constraint) getPkDDL() string {
+	var ddl strings.Builder
+	ddl.WriteString("CONSTRAINT ")
+	ddl.WriteString(c.Name)
+	ddl.WriteString(" PRIMARY KEY(")
+	for i, col := range c.Columns {
+		if i != 0 {
+			ddl.WriteString(", ")
+		}
+		ddl.WriteString(col.Name)
+	}
+	ddl.WriteString(")")
+	return ddl.String()
+}
+
+func (c *Constraint) getFkDDL() string {
+	var ddl strings.Builder
+	ddl.WriteString("CONSTRAINT ")
+	ddl.WriteString(c.Name)
+	ddl.WriteString(" FOREIGN KEY(")
+
+	for i, col := range c.Columns {
+		if i != 0 {
+			ddl.WriteString(", ")
+		}
+		ddl.WriteString(col.Name)
+	}
+
+	ddl.WriteString(") REFERENCES ")
+	ddl.WriteString(util.CamelToSnake(c.RefTypeName))
+	ddl.WriteString("(")
+
+	for i, col := range c.RefColumns {
+		if i != 0 {
+			ddl.WriteString(", ")
+		}
+		ddl.WriteString(col.Name)
+	}
+
+	ddl.WriteString(")")
+
+	return ddl.String()
+}
+
+func (Constraint) GetSelectDML() (string, error) {
+	return "", errors.New("No DML for constraints")
+}
+
+func (Constraint) GetInsertDML() (string, error) {
+	return "", errors.New("No DML for constraints")
+}
+
+func (Constraint) GetUpdateDML() (string, error) {
+	return "", errors.New("No DML for constraints")
+}
+
+func (Constraint) GetDeleteDML() (string, error) {
+	return "", errors.New("No DML for constraints")
+}

schema/parser.go

@@ -0,0 +1,103 @@
+package schema
+
+import (
+	"reflect"
+	"strings"
+
+	"git.gdulai.com/gdulai/simpleorm/util"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+type Parser struct {
+	typ         reflect.Type
+	columns     []Column
+	constraints []Constraint
+}
+
+func NewParser[T any](obj T) *Parser {
+	objType := reflect.TypeOf(obj)
+	return &Parser{typ: objType}
+}
+
+// Step 1 of the parsing, it creates the table instance and
+func (p *Parser) ParseColumns() {
+	var columns []Column
+	for field := range p.typ.Fields() {
+		field := field
+		col := NewColumn(util.CamelToSnake((field.Name)), field.Name, determineType(field.Type), field.Tag)
+		columns = append(columns, col)
+	}
+	p.columns = columns
+}
+
+// Step 2 of the parsing, it creates the constrains with the table references
+func (p *Parser) ParseConstraints(tableParsers map[string]*Parser) {
+	pkConstraint := Constraint{Name: "pk_" + strings.ToLower(util.CamelToSnake((p.typ.Name()))), Type: "pk"}
+	fkConstraints := make(map[string]Constraint)
+	for _, col := range p.columns {
+		_, ok := col.Modifiers["pk"]
+		if ok {
+			pkConstraint.Columns = append(pkConstraint.Columns, col)
+			continue
+		}
+
+		fkMod, ok := col.Modifiers["fk"]
+		if !ok {
+			continue
+		}
+
+		fkModParts := strings.Split(fkMod, ".")
+		refTypeName := fkModParts[0]
+		refTableName := util.CamelToSnake(refTypeName)
+		parser, ok := tableParsers[refTypeName]
+		if !ok {
+			log.LogError("[ORM] Reference table not found", refTypeName)
+		}
+
+		fkId, ok := col.Modifiers["fk_id"]
+		if fkId == "" {
+			fkId = "fk_" + strings.ToLower(refTableName)
+		}
+
+		fkConstraint, ok := fkConstraints[fkId]
+		if !ok {
+			fkConstraint = Constraint{Name: fkId, Type: "fk", RefTypeName: refTypeName}
+		}
+
+		fkConstraint.Columns = append(fkConstraint.Columns, col)
+
+		refField := fkModParts[1]
+		for _, refC := range parser.columns {
+			if refC.FieldName == refField {
+				fkConstraint.RefColumns = append(fkConstraint.RefColumns, refC)
+			}
+		}
+
+		fkConstraints[fkId] = fkConstraint
+	}
+
+	p.constraints = append(p.constraints, pkConstraint)
+	for _, fkConstraint := range fkConstraints {
+		p.constraints = append(p.constraints, fkConstraint)
+	}
+}
+
+// Step 3 of the paring, create the schema.Table instance
+// Returns the schema.Table pointer
+func (p Parser) ParseTable() *Table {
+	return &Table{name: util.CamelToSnake(p.typ.Name()), typ: p.typ, columns: p.columns, constraints: p.constraints}
+}
+
+func determineType(typ reflect.Type) string {
+	typStr := typ.String()
+	switch typStr {
+	case "string":
+		return "TEXT"
+	case "int", "bool":
+		return "INTEGER"
+	case "time.Time", "int64":
+		return "BIGINT"
+	}
+
+	return "VARCHAR(255)"
+}

schema/schema.go

@@ -0,0 +1,11 @@
+package schema
+
+// Interface that descibes a DB schema descripotor part.
+// eg.: Table, Column, Constraints etc.
+type SchemaDescriptor interface {
+	getDDL() (string, error)
+	GetSelectDML() (string, error)
+	GetInsertDML(count int) (string, error)
+	GetUpdateDML() (string, error)
+	GetDeleteDML(count int) (string, error)
+}

schema/table.go

@@ -0,0 +1,256 @@
+package schema
+
+import (
+	"errors"
+	"reflect"
+	"strings"
+
+	"git.gdulai.com/gdulai/simpleorm/util"
+)
+
+type OrderBy struct {
+	Field     string
+	Direction string
+}
+
+type Table struct {
+	name        string
+	typ         reflect.Type
+	columns     []Column
+	constraints []Constraint
+}
+
+func (t Table) Name() string {
+	return t.name
+}
+
+func (t Table) Type() reflect.Type {
+	return t.typ
+}
+
+func (t Table) Columns() []Column {
+	return t.columns
+}
+
+func (t Table) Constraints() []Constraint {
+	return t.constraints
+}
+
+func (t Table) GetDDL() (string, error) {
+	var ddl strings.Builder
+	ddl.WriteString("CREATE TABLE IF NOT EXISTS ")
+	ddl.WriteString(t.name)
+	ddl.WriteString(" (")
+	for i, col := range t.columns {
+		if i != 0 {
+			ddl.WriteString(", ")
+		}
+		colDdl, err := col.GetDDL()
+		if err != nil {
+			return "", err
+		}
+		ddl.WriteString(colDdl)
+	}
+	for _, constr := range t.constraints {
+		constrDdl, err := constr.GetDDL()
+		if err != nil {
+			return "", err
+		}
+		ddl.WriteString(", ")
+		ddl.WriteString(constrDdl)
+	}
+
+	ddl.WriteString(");")
+	return ddl.String(), nil
+}
+
+func (t Table) GetSelectDML() (string, error) {
+	var dml strings.Builder
+	dml.WriteString("SELECT ")
+
+	for i, col := range t.columns {
+		if i != 0 {
+			dml.WriteString(", ")
+		}
+		colDml, err := col.GetSelectDML()
+		if err != nil {
+			return "", err
+		}
+		dml.WriteString(colDml)
+	}
+
+	dml.WriteString(" FROM ")
+	dml.WriteString(t.name)
+	return dml.String(), nil
+}
+
+func (t Table) GetCountDML() string {
+	return "SELECT COUNT(*) FROM " + t.name
+}
+
+func (t Table) GetInsertDML(count int) (string, error) {
+	var dml strings.Builder
+	dml.WriteString("INSERT INTO ")
+	dml.WriteString(util.CamelToSnake(t.typ.Name()))
+	dml.WriteString(" (")
+
+	columnsLen := len(t.columns)
+	effectiveColumnsLen := 0
+	for i, col := range t.columns {
+		_, ok := col.Modifiers["pk"]
+		if ok && t.IsPkAuto() {
+			continue
+		}
+
+		colDml, err := col.GetInsertDML()
+		if err != nil {
+			return "", err
+		}
+
+		dml.WriteString(colDml)
+		if i != columnsLen-1 {
+			dml.WriteString(", ")
+		}
+		effectiveColumnsLen++
+	}
+
+	dml.WriteString(") VALUES")
+
+	for i := range count {
+		if i != 0 {
+			dml.WriteString(", ")
+		}
+		for j := range effectiveColumnsLen {
+			if j == 0 {
+				dml.WriteString("(")
+			}
+			if j != effectiveColumnsLen-1 {
+				dml.WriteString("?, ")
+			} else {
+				dml.WriteString("?)")
+			}
+		}
+	}
+
+	dml.WriteString(" RETURNING *")
+
+	return dml.String(), nil
+}
+
+func (t Table) GetUpdateDML() (string, error) {
+	var dml strings.Builder
+	dml.WriteString("UPDATE  ")
+	dml.WriteString(util.CamelToSnake(t.typ.Name()))
+	dml.WriteString(" SET ")
+
+	colLen := len(t.columns)
+	var pkColumns []string
+	// Colum names
+	for i, col := range t.columns {
+		modifiers := col.Modifiers
+
+		_, ok := modifiers["pk"]
+		if ok {
+			pkColumns = append(pkColumns, col.Name)
+			if t.IsPkAuto() {
+				continue
+			}
+		}
+
+		colDml, err := col.GetUpdateDML()
+		if err != nil {
+			return "", err
+		}
+
+		if i != colLen-1 {
+			dml.WriteString(colDml)
+			dml.WriteString(", ")
+		} else {
+			dml.WriteString(colDml)
+			dml.WriteString(" ")
+		}
+	}
+
+	dml.WriteString("WHERE ")
+
+	for i, pkCol := range pkColumns {
+		if i != 0 {
+			dml.WriteString(" AND ")
+		}
+		dml.WriteString(pkCol)
+		dml.WriteString(" = ?")
+	}
+
+	return dml.String(), nil
+}
+
+func (t Table) GetDeleteDML(count int) (string, error) {
+	var dml strings.Builder
+	dml.WriteString("DELETE FROM ")
+	dml.WriteString(t.name)
+	dml.WriteString(" WHERE ")
+
+	for _, col := range t.columns {
+		modifiers := col.Modifiers
+
+		_, ok := modifiers["pk"]
+		if ok {
+			if count > 1 {
+				dml.WriteString(col.Name)
+				dml.WriteString(" IN (")
+			} else {
+				dml.WriteString(col.Name)
+				dml.WriteString(" = ")
+			}
+		}
+	}
+
+	for i := range count {
+		if i != 0 {
+			dml.WriteString(", ")
+		}
+		dml.WriteString("?")
+	}
+
+	if count > 1 {
+		dml.WriteString(")")
+	}
+
+	return dml.String(), nil
+}
+
+func (t Table) GetOrderByDML(ordering ...OrderBy) (string, error) {
+	var dml strings.Builder
+	dml.WriteString(" ORDER BY")
+	for _, orderBy := range ordering {
+		col, err := t.getColumnByField(orderBy.Field)
+		if err != nil {
+			return "", err
+		}
+		dml.WriteString(" ")
+		dml.WriteString(col.Name)
+		dml.WriteString(" ")
+		dml.WriteString(orderBy.Direction)
+	}
+	return dml.String(), nil
+}
+
+func (t Table) getColumnByField(fieldName string) (Column, error) {
+	for _, col := range t.columns {
+		if col.FieldName == fieldName {
+			return col, nil
+		}
+	}
+	return Column{}, errors.New("No column for field " + fieldName + " in table " + t.name)
+}
+
+func (t Table) IsPkAuto() bool {
+	for _, constr := range t.constraints {
+		if constr.Type != "pk" {
+			continue
+		}
+
+		return len(constr.Columns) == 1
+	}
+	return true
+}

table.go

@@ -1,185 +0,0 @@
-package simpleorm
-
-import (
-	"errors"
-	"reflect"
-	"strings"
-	"time"
-)
-
-type Table struct {
-	Name        string
-	Type        reflect.Type
-	Columns     []Column
-	Constraints []Constraint
-}
-
-func (t Table) ToDDL() string {
-	var ddl strings.Builder
-	ddl.WriteString("CREATE TABLE IF NOT EXISTS " + t.Name + " (")
-	for i, col := range t.Columns {
-		if i != 0 {
-			ddl.WriteString(", ")
-		}
-		ddl.WriteString(col.ToDDL())
-	}
-	for _, constr := range t.Constraints {
-		ddl.WriteString(", " + constr.ToDDL())
-	}
-
-	ddl.WriteString(");")
-	return ddl.String()
-}
-
-func (t Table) ToSelectDML() string {
-	var dml strings.Builder
-	dml.WriteString("SELECT ")
-
-	for i, col := range t.Columns {
-		if i != 0 {
-			dml.WriteString(", ")
-		}
-		dml.WriteString(col.Name)
-	}
-
-	dml.WriteString(" FROM " + t.Name)
-	return dml.String()
-}
-
-func (t Table) ToInsertDML(count int) string {
-	var dml strings.Builder
-	dml.WriteString("INSERT INTO " + camelToSnake(t.Type.Name()) + " (")
-
-	columnsLen := len(t.Columns)
-	effectiveColumnsLen := 0
-	for i, col := range t.Columns {
-		_, ok := col.Modifiers["pk"]
-		if ok {
-			continue
-		}
-
-		dml.WriteString(col.Name)
-		if i != columnsLen-1 {
-			dml.WriteString(", ")
-		}
-		effectiveColumnsLen++
-	}
-
-	dml.WriteString(") VALUES")
-
-	for i := range count {
-		if i != 0 {
-			dml.WriteString(", ")
-		}
-		for j := range effectiveColumnsLen {
-			if j == 0 {
-				dml.WriteString("(")
-			}
-			if j != effectiveColumnsLen-1 {
-				dml.WriteString("?, ")
-			} else {
-				dml.WriteString("?)")
-			}
-		}
-	}
-
-	return dml.String()
-}
-
-func (t Table) ToUpdateDML(src any) string {
-	var dml strings.Builder
-	dml.WriteString("UPDATE  " + camelToSnake(t.Type.Name()) + " SET ")
-
-	var pkCol string
-	// Colum names
-	for i := 0; i < t.Type.NumField(); i++ {
-		field := t.Type.Field(i)
-		modifiers := determineModifiers(field.Tag)
-
-		_, ok := modifiers["pk"]
-		if ok {
-			pkCol = camelToSnake(field.Name)
-			continue
-		}
-
-		if i != t.Type.NumField()-1 {
-			dml.WriteString(camelToSnake(field.Name) + " = ?, ")
-		} else {
-			dml.WriteString(camelToSnake(field.Name) + " = ? ")
-		}
-
-	}
-
-	dml.WriteString("WHERE " + pkCol + " = ?")
-
-	return dml.String()
-}
-
-func (t Table) ToDeleteDML(src any) string {
-	var dml strings.Builder
-	dml.WriteString("DELETE FROM " + camelToSnake(t.Type.Name()) + " WHERE ")
-
-	for i := 0; i < t.Type.NumField(); i++ {
-		field := t.Type.Field(i)
-		modifiers := determineModifiers(field.Tag)
-		_, ok := modifiers["pk"]
-		if ok {
-			dml.WriteString(camelToSnake(field.Name) + " = ?")
-			return dml.String()
-		}
-	}
-
-	return ""
-}
-
-func (t Table) createSelectResultContainer() []any {
-	vals := make([]any, t.Type.NumField())
-	for i := range vals {
-		switch t.Type.Field(i).Type.Kind().String() {
-		case "string":
-			var fieldContainer string
-			vals[i] = &fieldContainer
-		case "int":
-			var fieldContainer int
-			vals[i] = &fieldContainer
-		case "int64", "time.Time":
-			var fieldContainer int64
-			vals[i] = &fieldContainer
-		}
-	}
-	return vals
-}
-
-func (t Table) prepareParams(src any) []any {
-	var params []any
-	for i := 0; i < t.Type.NumField(); i++ {
-		field := t.Type.Field(i)
-		modifiers := determineModifiers(field.Tag)
-		_, ok := modifiers["pk"]
-		if ok {
-			continue
-		}
-		typStr := field.Type.String()
-		switch typStr {
-		case "time.Time":
-			time := reflect.ValueOf(src).Field(i).Interface().(time.Time)
-			params = append(params, time.UnixMilli())
-		default:
-			params = append(params, reflect.ValueOf(src).Field(i).Interface())
-		}
-	}
-
-	return params
-}
-
-func (t Table) getPk(src any) (any, error) {
-	for i := 0; i < t.Type.NumField(); i++ {
-		field := t.Type.Field(i)
-		modifiers := determineModifiers(field.Tag)
-		_, ok := modifiers["pk"]
-		if ok {
-			return reflect.ValueOf(src).Field(i).Interface(), nil
-		}
-	}
-	return nil, errors.New("Could not determine pk column!")
-}

test/exec_test.go

@@ -0,0 +1,565 @@
+package simpleorm_test
+
+import (
+	"strconv"
+	"testing"
+	"time"
+
+	"git.gdulai.com/gdulai/simpleorm/exec"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+func TestInsert(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	insertErr := insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertAndSelectSingle insert failed: %s", err)
+		t.Fail()
+		return
+	}
+	insertRes := insertExec.Results()
+
+	// THEN
+	if insertErr != nil {
+		log.LogError("TestInsertAndSelectSingle failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	if len(insertRes) != 1 {
+		log.LogError("TestInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(insertRes))
+		t.Fail()
+		return
+	}
+
+	singleRes := insertRes[0]
+	if singleRes.ID != 1 || singleRes.Int64Field != 54 || singleRes.IntField != 12 || singleRes.StringField != "asdf" {
+		log.LogError("TestInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+}
+
+func TestInsertMultiple(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+	testObjSecond := Test{Int64Field: 12, IntField: 54, StringField: "fdsa"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert[Test](orm, testObj, testObjSecond)
+	if err != nil {
+		log.LogError("TestInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	insertErr := insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertAndSelectSingle insert failed: %s", err)
+		t.Fail()
+		return
+	}
+	insertRes := insertExec.Results()
+
+	// THEN
+	if insertErr != nil {
+		log.LogError("TestInsertAndSelectSingle failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	if len(insertRes) != 2 {
+		log.LogError("TestInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(insertRes))
+		t.Fail()
+		return
+	}
+
+	entity := insertRes[0]
+	if entity.ID != 1 || entity.Int64Field != 54 || entity.IntField != 12 || entity.StringField != "asdf" {
+		log.LogError("TestInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, entity)
+		t.Fail()
+	}
+
+	entity = insertRes[1]
+	if entity.ID != 2 || entity.Int64Field != 12 || entity.IntField != 54 || entity.StringField != "fdsa" {
+		log.LogError("TestInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObjSecond, entity)
+		t.Fail()
+	}
+
+}
+
+func TestInsertAndUpdate(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertAndUpdate setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec.Where("string_field = ?", "asdf")
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertAndUpdate insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertAndUpdate re-select failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	res := selectExec.Results()
+	testObj = res[0]
+
+	testObj.IntField = 42069
+	testObj.Int64Field = 69420
+
+	updateExec, err := exec.NewUpdate(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertAndUpdate setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = updateExec.Execute(conn)
+	selectErr := selectExec.Execute(conn)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestInsertAndUpdate update failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	if selectErr != nil {
+		log.LogError("TestInsertAndUpdate select failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	res = selectExec.Results()
+	if len(res) != 1 {
+		log.LogError("TestInsertAndUpdate test failed. Expected: 1, Actual: %s", len(res))
+		t.Fail()
+		return
+	}
+
+	singleRes := res[0]
+	if singleRes.ID != 1 || singleRes.Int64Field != 69420 || singleRes.IntField != 42069 || singleRes.StringField != "asdf" {
+		log.LogError("TestInsertAndUpdate invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+
+}
+
+func TestInsertAndDelete(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertAndDelete setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertAndDelete setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestInsertAndDelete setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertAndDelete setup failed. %s", err)
+		t.Fail()
+		return
+	}
+
+	deleteExec, err := exec.NewDelete(orm, selectExec.Results())
+	err = deleteExec.Execute(conn)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestInsertAndDelete delete failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+	// THEN
+	if err != nil {
+		log.LogError("TestInsertAndDelete delete failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	selectRes := selectExec.Results()
+	if len(selectRes) != 0 {
+		log.LogError("TestInsertAndDelete test failed. Expected: 0, Actual: %s", len(selectRes))
+		t.Fail()
+		return
+	}
+
+}
+
+func TestBoolInsertAndSelectSingle(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := TestWithBool{BoolField: true}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestBoolInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[TestWithBool](orm)
+	if err != nil {
+		log.LogError("TestBoolInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestBoolInsertAndSelectSingle insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestBoolInsertAndSelectSingle failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	res := selectExec.Results()
+	if len(res) != 1 {
+		log.LogError("TestBoolInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(res))
+		t.Fail()
+		return
+	}
+
+	singleRes := res[0]
+	if singleRes.ID != 1 || !singleRes.BoolField {
+		log.LogError("TestBoolInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+
+}
+
+func TestTimeInsertAndSelectSingle(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	now := time.Now().UnixMilli()
+	testObj := TestWithTime{TimeField: now}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestTimeInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[TestWithTime](orm)
+	if err != nil {
+		log.LogError("TestTimeInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestTimeInsertAndSelectSingle insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestTimeInsertAndSelectSingle failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	res := selectExec.Results()
+	if len(res) != 1 {
+		log.LogError("TestTimeInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(res))
+		t.Fail()
+		return
+	}
+
+	singleRes := res[0]
+	if singleRes.ID != 1 || singleRes.TimeField != now {
+		log.LogError("TestTimeInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+
+}
+
+func TestTransactionExecuteSimple(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	transaction := exec.NewTransaction(conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert[Test](orm, testObj)
+	if err != nil {
+		log.LogError("TestTransactionExecuteSimple failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	transErr := transaction.Execute(&insertExec)
+	if transErr != nil {
+		transErr = transaction.Finish()
+	}
+
+	// THEN
+	if transErr != nil {
+		log.LogError("TestTransactionExecuteSimple failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	insertRes := insertExec.Results()
+
+	if len(insertRes) != 1 {
+		log.LogError("TestInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(insertRes))
+		t.Fail()
+		return
+	}
+
+	singleRes := insertRes[0]
+	if singleRes.ID != 1 || singleRes.Int64Field != 54 || singleRes.IntField != 12 || singleRes.StringField != "asdf" {
+		log.LogError("TestInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+}
+
+func TestTransactionRollback(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	transaction := exec.NewTransaction(conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert[Test](orm, testObj)
+	if err != nil {
+		log.LogError("TestTransactionRollback WHEN failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	transErr := transaction.Execute(&insertExec)
+	if transErr != nil {
+		log.LogError("TestTransactionRollback WHEN failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestTransactionRollback WHEN failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec.Where("id = ?", insertExec.Results()[0].ID)
+
+	transErr = transaction.Execute(&selectExec)
+	if transErr != nil {
+		log.LogError("TestTransactionRollback WHEN failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	beforeRollbackSelectRes := selectExec.Results()
+	rollbackErr := transaction.Rollback()
+	afterRollbackErr := selectExec.Execute(conn)
+	afterRollbackSelectRes := selectExec.Results()
+
+	// THEN
+	if len(beforeRollbackSelectRes) != 1 {
+		log.LogError("TestTransactionExecuteSimple-THEN: Expected 1, Actual: %s", len(beforeRollbackSelectRes))
+		t.Fail()
+		return
+	}
+
+	if rollbackErr != nil {
+		log.LogError("TestTransactionExecuteSimple-THEN: rollback error: %s", rollbackErr)
+		t.Fail()
+		return
+	}
+
+	if afterRollbackErr != nil {
+		log.LogError("TestTransactionExecuteSimple-THEN: after rollback select error: %s", rollbackErr)
+		t.Fail()
+		return
+	}
+
+	if len(afterRollbackSelectRes) != 0 {
+		log.LogError("TestTransactionExecuteSimple-THEN: Expected 0 after rollback select result")
+		t.Fail()
+		return
+	}
+}
+
+func TestCount(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testEntites := []Test{}
+
+	for i := 0; i < 1000; i++ {
+		testEntites = append(testEntites, Test{Int64Field: -1, IntField: i, StringField: "Entity " + strconv.Itoa(i)})
+	}
+
+	insertExec, err := exec.NewInsert[Test](orm, testEntites...)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset setup failed: %s", err)
+		t.Fail()
+		return
+	}
+	// WHEN
+
+	countExec, err := exec.CreateCount[Test](orm, "")
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset failed: %s", err)
+		t.Fail()
+		return
+	}
+	err = countExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// THEN
+
+	if countExec.Result() != 1000 {
+		log.LogError("TestSelectWithLimitAndOffset expected result size 1000, actual: %s", countExec.Result())
+		t.Fail()
+	}
+}
+
+func TestCountWithCondition(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testEntites := []Test{}
+
+	for i := 0; i < 1000; i++ {
+		testEntites = append(testEntites, Test{Int64Field: -1, IntField: i, StringField: "Entity " + strconv.Itoa(i)})
+	}
+
+	insertExec, err := exec.NewInsert[Test](orm, testEntites...)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset setup failed: %s", err)
+		t.Fail()
+		return
+	}
+	// WHEN
+
+	countExec, err := exec.CreateCount[Test](orm, "id % 2 = 0")
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset failed: %s", err)
+		t.Fail()
+		return
+	}
+	err = countExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// THEN
+
+	if countExec.Result() != 500 {
+		log.LogError("TestSelectWithLimitAndOffset expected result size 500, actual: %s", countExec.Result())
+		t.Fail()
+	}
+}

test/main_test.go

@@ -0,0 +1,87 @@
+package simpleorm_test
+
+import (
+	"os"
+	"testing"
+
+	simpleorm "git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/exec"
+	_ "github.com/mattn/go-sqlite3"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+type Test struct {
+	ID          int    `sql:"pk"`
+	Int64Field  int64  `sql:"nn"`
+	IntField    int    `sql:"nn"`
+	StringField string `sql:"nn"`
+}
+
+func (t Test) IsInsertable() bool {
+	return t.ID == 0
+}
+
+type TestWithFk struct {
+	ID     int `sql:"pk"`
+	TestID int `sql:"nn;fk=Test.ID"`
+}
+
+type TestWithFkAndFkId struct {
+	ID     int `sql:"pk"`
+	TestID int `sql:"nn;fk=Test.ID;fk_id=custom_fk"`
+}
+
+type TestWithCompositePk struct {
+	ID   int    `sql:"nn;pk;"`
+	Name string `sql:"nn;pk"`
+}
+
+func (t TestWithCompositePk) IsInsertable() bool {
+	return t.ID == 0 && t.Name == ""
+}
+
+type TestWithCompositeFk struct {
+	ID              int    `sql:"nn;pk"`
+	CompositeFkId   int    `sql:"nn;fk=TestWithCompositePk.ID;"`
+	CompositeFkName string `sql:"nn;fk=TestWithCompositePk.Name;"`
+}
+
+type TestWithBool struct {
+	ID        int  `sql:"pk"`
+	BoolField bool `sql:"nn"`
+}
+
+type TestWithTime struct {
+	ID        int   `sql:"pk"`
+	TimeField int64 `sql:"nn"`
+}
+
+type TestWithJsonStructTag struct {
+	ID          int    `json:"id" sql:"pk"`
+	Int64Field  int64  `json:"int64Field" sql:"nn"`
+	IntField    int    `json:"intField" sql:"nn"`
+	StringField string `json:"stringField" sql:"nn"`
+}
+
+func TestMain(m *testing.M) {
+	log.SetupLogs("Info")
+
+	code := m.Run()
+
+	os.Exit(code)
+}
+
+func testSetup() (*simpleorm.ORM, *simpleorm.DBConnection) {
+	conn := simpleorm.OpenConnection("sqlite3", "file:test.db")
+
+	orm := simpleorm.NewORM(Test{}, TestWithFk{}, TestWithFkAndFkId{},
+		TestWithCompositePk{}, TestWithCompositeFk{}, TestWithBool{}, TestWithTime{})
+	exec.ExecuteDDL(conn, orm)
+
+	return orm, conn
+}
+
+func cleanUp(dbFile string, conn *simpleorm.DBConnection) {
+	conn.Close()
+	os.Remove(dbFile)
+}

test/repository_test.go

@@ -0,0 +1,135 @@
+package simpleorm_test
+
+import (
+	"testing"
+
+	"git.gdulai.com/gdulai/simpleorm/exec"
+	"git.gdulai.com/gdulai/simpleorm/repository"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+func TestRepoSelectAll(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestRepoSelectAll setup failed: %s", err)
+		t.Fail()
+		return
+	}
+	err = insertExec.Execute(conn)
+	repo := repository.NewRepository[Test](conn, orm)
+
+	// WHEN
+	res := repo.SelectAll()
+
+	// THEN
+	if len(res) != 1 {
+		log.LogError("TestRepoSelectAll test failed. Expected: 1, Actual: %s", len(res))
+		t.Fail()
+		return
+	}
+}
+
+func TestRepoSelectByPk(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestRepoSelectByPk setup failed: %s", err)
+		t.Fail()
+		return
+	}
+	err = insertExec.Execute(conn)
+	repo := repository.NewRepository[Test](conn, orm)
+
+	// WHEN
+	res := repo.SelectByPk(1)
+
+	// THEN
+	if res == nil {
+		log.LogError("TestRepoSelectByPk test failed. Result is nil!")
+		t.Fail()
+		return
+	}
+}
+
+func TestRepoSelectByCompundPk(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := TestWithCompositePk{ID: 42069, Name: "Test"}
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestRepoSelectByCompundPk setup failed: %s", err)
+		t.Fail()
+		return
+	}
+	err = insertExec.Execute(conn)
+	repo := repository.NewRepository[TestWithCompositePk](conn, orm)
+
+	// WHEN
+	res := repo.SelectByPk(42069, "Test")
+
+	// THEN
+	if res == nil {
+		log.LogError("TestRepoSelectByCompundPk test failed. Result is nil!")
+		t.Fail()
+		return
+	}
+}
+
+func TestRepoSave(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := &Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+	repo := repository.NewRepository[Test](conn, orm)
+
+	// WHEN
+	err := repo.Save(testObj)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestRepoSave failed: %s", err)
+	}
+	if testObj.ID == 0 {
+		log.LogError("TestRepoSave failed! testObj.ID is 0!")
+		t.Fail()
+	}
+}
+
+func TestRepoDelete(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := &Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+	repo := repository.NewRepository[Test](conn, orm)
+
+	err := repo.Save(testObj)
+	if err != nil {
+		log.LogError("TestRepoDelete setup failed! Test data not saved!")
+		t.Fail()
+		return
+	}
+
+	// WHEN
+	repo.Delete(testObj)
+
+	// THEN
+	res := repo.SelectByPk(testObj.ID)
+	if res != nil {
+		log.LogError("TestRepoDelete test failed. Result is not nil!")
+		t.Fail()
+		return
+	}
+}

test/schema_test.go

@@ -1,10 +1,10 @@
 package simpleorm_test
 
 import (
-	"simpleorm"
 	"strconv"
 	"testing"
 
+	simpleorm "git.gdulai.com/gdulai/simpleorm"
 	log "gitlab.com/gdulai/simpleloglvl"
 )
 
@@ -13,8 +13,13 @@ func TestParseSimple(t *testing.T) {
 	// GIVEN
 	orm := simpleorm.NewORM(Test{})
 	// WHEN
-	ddl := orm.CreateDDL()
+	ddl, err := orm.CreateSchema()
 	// THEN
+	if err != nil {
+		log.LogError("Failed to parse schema! %s", err)
+		t.Fail()
+	}
+
 	expectedDdl := "CREATE TABLE IF NOT EXISTS TEST (ID INTEGER, INT64_FIELD BIGINT NOT NULL, INT_FIELD INTEGER NOT NULL, STRING_FIELD TEXT NOT NULL, CONSTRAINT pk_test PRIMARY KEY(ID));"
 	if ddl != expectedDdl {
 		log.LogError("Incorrect DDL.\nExpected\n%s\nActual\n%s", expectedDdl, ddl)
@@ -29,8 +34,13 @@ func TestParseFk(t *testing.T) {
 	// GIVEN
 	orm := simpleorm.NewORM(Test{}, TestWithFk{})
 	// WHEN
-	ddl := orm.CreateDDL()
+	ddl, err := orm.CreateSchema()
 	// THEN
+	if err != nil {
+		log.LogError("Failed to parse schema! %s", err)
+		t.Fail()
+	}
+
 	expectedDdl :=
 		"CREATE TABLE IF NOT EXISTS TEST (ID INTEGER, INT64_FIELD BIGINT NOT NULL, INT_FIELD INTEGER NOT NULL, STRING_FIELD TEXT NOT NULL, CONSTRAINT pk_test PRIMARY KEY(ID));\n" +
 			"CREATE TABLE IF NOT EXISTS TEST_WITH_FK (ID INTEGER, TEST_ID INTEGER NOT NULL, CONSTRAINT pk_test_with_fk PRIMARY KEY(ID), CONSTRAINT fk_test FOREIGN KEY(TEST_ID) REFERENCES TEST(ID));"
@@ -46,8 +56,14 @@ func TestParseFkAndFkId(t *testing.T) {
 	// GIVEN
 	orm := simpleorm.NewORM(Test{}, TestWithFkAndFkId{})
 	// WHEN
-	ddl := orm.CreateDDL()
+	// WHEN
+	ddl, err := orm.CreateSchema()
 	// THEN
+	if err != nil {
+		log.LogError("Failed to parse schema! %s", err)
+		t.Fail()
+	}
+
 	expectedDdl :=
 		"CREATE TABLE IF NOT EXISTS TEST (ID INTEGER, INT64_FIELD BIGINT NOT NULL, INT_FIELD INTEGER NOT NULL, STRING_FIELD TEXT NOT NULL, CONSTRAINT pk_test PRIMARY KEY(ID));\n" +
 			"CREATE TABLE IF NOT EXISTS TEST_WITH_FK_AND_FK_ID (ID INTEGER, TEST_ID INTEGER NOT NULL, CONSTRAINT pk_test_with_fk_and_fk_id PRIMARY KEY(ID), CONSTRAINT custom_fk FOREIGN KEY(TEST_ID) REFERENCES TEST(ID));"
@@ -62,8 +78,13 @@ func TestParseCompositePk(t *testing.T) {
 	// GIVEN
 	orm := simpleorm.NewORM(TestWithCompositePk{})
 	// WHEN
-	ddl := orm.CreateDDL()
+	ddl, err := orm.CreateSchema()
 	// THEN
+	if err != nil {
+		log.LogError("Failed to parse schema! %s", err)
+		t.Fail()
+	}
+
 	expectedDdl := "CREATE TABLE IF NOT EXISTS TEST_WITH_COMPOSITE_PK (ID INTEGER NOT NULL, NAME TEXT NOT NULL, CONSTRAINT pk_test_with_composite_pk PRIMARY KEY(ID, NAME));"
 	if ddl != expectedDdl {
 		log.LogError("Incorrect DDL.\nExpected\n%s\nActual\n%s", expectedDdl, ddl)
@@ -76,8 +97,13 @@ func TestParseCompositeFk(t *testing.T) {
 	// GIVEN
 	orm := simpleorm.NewORM(TestWithCompositePk{}, TestWithCompositeFk{})
 	// WHEN
-	ddl := orm.CreateDDL()
+	ddl, err := orm.CreateSchema()
 	// THEN
+	if err != nil {
+		log.LogError("Failed to parse schema! %s", err)
+		t.Fail()
+	}
+
 	expectedDdl :=
 		"CREATE TABLE IF NOT EXISTS TEST_WITH_COMPOSITE_PK (ID INTEGER NOT NULL, NAME TEXT NOT NULL, CONSTRAINT pk_test_with_composite_pk PRIMARY KEY(ID, NAME));\n" +
 			"CREATE TABLE IF NOT EXISTS TEST_WITH_COMPOSITE_FK (ID INTEGER NOT NULL, COMPOSITE_FK_ID INTEGER NOT NULL, COMPOSITE_FK_NAME TEXT NOT NULL, CONSTRAINT pk_test_with_composite_fk PRIMARY KEY(ID), CONSTRAINT fk_test_with_composite_pk FOREIGN KEY(COMPOSITE_FK_ID, COMPOSITE_FK_NAME) REFERENCES TEST_WITH_COMPOSITE_PK(ID, NAME));"
@@ -87,3 +113,23 @@ func TestParseCompositeFk(t *testing.T) {
 		t.Fail()
 	}
 }
+
+func TestParseStructWithJsonTag(t *testing.T) {
+	// GIVEN
+	orm := simpleorm.NewORM(TestWithJsonStructTag{})
+	// WHEN
+	ddl, err := orm.CreateSchema()
+	// THEN
+	if err != nil {
+		log.LogError("Failed to parse schema! %s", err)
+		t.Fail()
+	}
+
+	expectedDdl := "CREATE TABLE IF NOT EXISTS TEST_WITH_JSON_STRUCT_TAG (ID INTEGER, INT64_FIELD BIGINT NOT NULL, INT_FIELD INTEGER NOT NULL, STRING_FIELD TEXT NOT NULL, CONSTRAINT pk_test_with_json_struct_tag PRIMARY KEY(ID));"
+	if ddl != expectedDdl {
+		log.LogError("Incorrect DDL.\nExpected\n%s\nActual\n%s", expectedDdl, ddl)
+		log.LogError("\nExpected size: %s\nActual size: %s", strconv.Itoa(len(expectedDdl)), strconv.Itoa(len(ddl)))
+		t.Fail()
+	}
+	log.LogInfo("Test finished!")
+}

test/select_test.go

@@ -0,0 +1,419 @@
+package simpleorm_test
+
+import (
+	"strconv"
+	"testing"
+
+	simpleorm "git.gdulai.com/gdulai/simpleorm"
+	"git.gdulai.com/gdulai/simpleorm/exec"
+	"git.gdulai.com/gdulai/simpleorm/schema"
+	log "gitlab.com/gdulai/simpleloglvl"
+)
+
+func TestSelectEmpty(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	// WHEN
+	selectExec, err := exec.NewSelect[Test](orm)
+
+	// THEN
+	if err != nil {
+		log.LogError("Failed to create select. %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("Select failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	res := selectExec.Results()
+	if len(res) > 0 {
+		log.LogError("Expected empty result.")
+		t.Fail()
+		return
+	}
+}
+
+func TestSelectSingle(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestInsertAndSelectSingle setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	insertErr := insertExec.Execute(conn)
+	selectErr := selectExec.Execute(conn)
+
+	// THEN
+	if insertErr != nil {
+		log.LogError("TestInsertAndSelectSingle insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	if selectErr != nil {
+		log.LogError("TestInsertAndSelectSingle failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	insertRes := insertExec.Results()
+	if len(insertRes) != 1 {
+		log.LogError("TestInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(insertRes))
+		t.Fail()
+		return
+	}
+
+	selectRes := selectExec.Results()
+	if len(selectRes) != 1 {
+		log.LogError("TestInsertAndSelectSingle test failed. Expected: 1, Actual: %s", len(selectRes))
+		t.Fail()
+		return
+	}
+
+	singleRes := insertRes[0]
+	if singleRes.ID != 1 || singleRes.Int64Field != 54 || singleRes.IntField != 12 || singleRes.StringField != "asdf" {
+		log.LogError("TestInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+
+	singleRes = selectRes[0]
+	if singleRes.ID != 1 || singleRes.Int64Field != 54 || singleRes.IntField != 12 || singleRes.StringField != "asdf" {
+		log.LogError("TestInsertAndSelectSingle invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+
+}
+
+func TestSelectWithCompositePk(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testObj := TestWithCompositePk{ID: 12, Name: "Test"}
+
+	// WHEN
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertSelectWithCompositePk setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[TestWithCompositePk](orm)
+	if err != nil {
+		log.LogError("TestInsertSelectWithCompositePk setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertSelectWithCompositePk insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestInsertSelectWithCompositePk failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	res := selectExec.Results()
+	if len(res) != 1 {
+		log.LogError("TestInsertSelectWithCompositePk test failed. Expected: 1, Actual: %s", len(res))
+		t.Fail()
+		return
+	}
+
+	singleRes := res[0]
+	if singleRes.ID != 12 || singleRes.Name != "Test" {
+		log.LogError("TestInsertSelectWithCompositePk invalid result. Expected: %s, Actual: %s", testObj, singleRes)
+		t.Fail()
+	}
+
+}
+
+func TestSelectWithParam(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	// WHEN
+	testObj := Test{Int64Field: 54, IntField: 12, StringField: "asdf"}
+	testObjSecond := Test{Int64Field: 12, IntField: 54, StringField: "fdsa"}
+
+	insertExec, err := exec.NewInsert(orm, testObj)
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	insertSecond, err := exec.NewInsert(orm, testObjSecond)
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	selectExec.Where("string_field = ?", "fdsa")
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam first insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertSecond.Execute(conn)
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam second insert failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = selectExec.Execute(conn)
+
+	// THEN
+	if err != nil {
+		log.LogError("TestInsertMultipleAndSelectWithParam failure. %s", err)
+		t.Fail()
+		return
+	}
+
+	res := selectExec.Results()
+	if len(res) != 1 {
+		log.LogError(" TestInsertMultipleAndSelectWithParam test failed. Expected: 1, Actual: %s", len(res))
+		t.Fail()
+		return
+	}
+
+	singleRes := res[0]
+	if singleRes.ID != 2 || singleRes.Int64Field != 12 || singleRes.IntField != 54 || singleRes.StringField != "fdsa" {
+		log.LogError("TestInsertMultipleAndSelectWithParam invalid result. Expected: %s, Actual: %s", testObjSecond, singleRes)
+		t.Fail()
+		return
+	}
+}
+
+func TestSelectWithLimitAndOffset(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	testEntites := []Test{}
+
+	for i := 0; i < 1000; i++ {
+		testEntites = append(testEntites, Test{Int64Field: -1, IntField: i, StringField: "Entity " + strconv.Itoa(i)})
+	}
+
+	insertExec, err := exec.NewInsert[Test](orm, testEntites...)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset setup failed: %s", err)
+		t.Fail()
+		return
+	}
+	// WHEN
+
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset failed: %s", err)
+		t.Fail()
+		return
+	}
+	selectExec.Limit(100).Offset(0)
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectWithLimitAndOffset failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// THEN
+
+	if len(selectExec.Results()) != 100 {
+		log.LogError("TestSelectWithLimitAndOffset expected result size 100, actual: %s", len(selectExec.Results()))
+		t.Fail()
+	}
+}
+
+func TestSelectOrderByDesc(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	err := orderBySetup(conn, orm)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// WHEN
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestSelectOrderByDesc failed: %s", err)
+		t.Fail()
+		return
+	}
+	selectExec.OrderBy(schema.OrderBy{Field: "StringField", Direction: "DESC"})
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectOrderByDesc failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// THEN
+	var resultStr string
+	for _, obj := range selectExec.Results() {
+		resultStr += obj.StringField
+	}
+
+	if resultStr != "EDCBA" {
+		log.LogError("TestSelectOrderByDesc failed, epxected: EDCBA actual: %s", resultStr)
+		t.Fail()
+	}
+}
+
+func TestSelectOrderByAsc(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	err := orderBySetup(conn, orm)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// WHEN
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc failed: %s", err)
+		t.Fail()
+		return
+	}
+	selectExec.OrderBy(schema.OrderBy{Field: "StringField", Direction: "ASC"})
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// THEN
+	var resultStr string
+	for _, obj := range selectExec.Results() {
+		resultStr += obj.StringField
+	}
+
+	if resultStr != "ABCDE" {
+		log.LogError("TestSelectOrderByAsc failed, epxected: ABCDE actual: %s", resultStr)
+		t.Fail()
+	}
+}
+
+func TestSelectOrderByAscWithLimitAndOffset(t *testing.T) {
+	// GIVEN
+	orm, conn := testSetup()
+	defer cleanUp("test.db", conn)
+
+	err := orderBySetup(conn, orm)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc setup failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// WHEN
+	selectExec, err := exec.NewSelect[Test](orm)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc failed: %s", err)
+		t.Fail()
+		return
+	}
+	selectExec.OrderBy(schema.OrderBy{Field: "StringField", Direction: "ASC"}).Limit(3).Offset(0)
+
+	err = selectExec.Execute(conn)
+	if err != nil {
+		log.LogError("TestSelectOrderByAsc failed: %s", err)
+		t.Fail()
+		return
+	}
+
+	// THEN
+	var resultStr string
+	for _, obj := range selectExec.Results() {
+		resultStr += obj.StringField
+	}
+
+	if resultStr != "ABC" {
+		log.LogError("TestSelectOrderByAsc failed, epxected: ABC actual: %s", resultStr)
+		t.Fail()
+	}
+}
+
+func orderBySetup(conn *simpleorm.DBConnection, orm *simpleorm.ORM) error {
+	insertExec, err := exec.NewInsert[Test](orm,
+		Test{Int64Field: -1, IntField: 1, StringField: "C"},
+		Test{Int64Field: -1, IntField: 1, StringField: "D"},
+		Test{Int64Field: -1, IntField: 1, StringField: "E"},
+		Test{Int64Field: -1, IntField: 1, StringField: "A"},
+		Test{Int64Field: -1, IntField: 1, StringField: "B"},
+	)
+	if err != nil {
+		return err
+	}
+
+	err = insertExec.Execute(conn)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

util/util.go

@@ -0,0 +1,21 @@
+package util
+
+import (
+	"strings"
+	"unicode"
+)
+
+func CamelToSnake(str string) string {
+	var snake strings.Builder
+	isPrevUpper := true
+	for _, c := range str {
+		if unicode.IsUpper(c) && !isPrevUpper {
+			snake.WriteString("_" + string(unicode.ToUpper(c)))
+			isPrevUpper = true
+		} else {
+			snake.WriteString(string(unicode.ToUpper(c)))
+			isPrevUpper = unicode.IsUpper(c)
+		}
+	}
+	return snake.String()
+}