feature: Add support for LIMIT query in UPDATE for sql

Signed-off-by: Rohan Hasabe <rohanhasabe8@gmail.com>

mysql/update_statement.go

@@ -12,6 +12,7 @@ type UpdateStatement interface {
 	MODEL(data interface{}) UpdateStatement
 
 	WHERE(expression BoolExpression) UpdateStatement
+	LIMIT(limit int64) UpdateStatement
 }
 
 type updateStatementImpl struct {
@@ -21,6 +22,7 @@ type updateStatementImpl struct {
 	Set    jet.SetClause
 	SetNew jet.SetClauseNew
 	Where  jet.ClauseWhere
+	Limit  jet.ClauseLimit
 }
 
 func newUpdateStatement(table Table, columns []jet.Column) UpdateStatement {
@@ -29,11 +31,13 @@ func newUpdateStatement(table Table, columns []jet.Column) UpdateStatement {
 		&update.Update,
 		&update.Set,
 		&update.SetNew,
-		&update.Where)
+		&update.Where,
+		&update.Limit)
 
 	update.Update.Table = table
 	update.Set.Columns = columns
 	update.Where.Mandatory = true
+	update.Limit.Count = -1 // Initialize to -1 to indicate no LIMIT
 
 	return update
 }
@@ -67,3 +71,11 @@ func (u *updateStatementImpl) WHERE(expression BoolExpression) UpdateStatement {
 	u.Where.Condition = expression
 	return u
 }
+
+func (u *updateStatementImpl) LIMIT(limit int64) UpdateStatement {
+	if _, isJoinTable := u.Update.Table.(*joinTable); isJoinTable {
+		panic("jet: MySQL does not support LIMIT with multi-table UPDATE statements")
+	}
+	u.Limit.Count = limit
+	return u
+}

mysql/update_statement_test.go

@@ -6,6 +6,21 @@ import (
 	"testing"
 )
 
+func TestUpdateWithLimit(t *testing.T) {
+	expectedSQL := `
+UPDATE db.table1
+SET col_int = ?
+WHERE table1.col_int >= ?
+LIMIT ?;
+`
+	stmt := table1.UPDATE(table1ColInt).
+		SET(1).
+		WHERE(table1ColInt.GT_EQ(Int(33))).
+		LIMIT(5)
+
+	assertStatementSql(t, stmt, expectedSQL, 1, int64(33), int64(5))
+}
+
 func TestUpdateWithOneValue(t *testing.T) {
 	expectedSQL := `
 UPDATE db.table1
@@ -69,11 +84,26 @@ func TestUpdateReservedWorldColumn(t *testing.T) {
 					Load: "foo",
 				},
 			).
-			WHERE(loadColumn.EQ(String("bar"))), strings.Replace(`
+			WHERE(loadColumn.EQ(String("bar"))).
+			LIMIT(0),
+		strings.Replace(`
 UPDATE db.table1
 SET ''Load'' = ?
-WHERE ''Load'' = ?;
+WHERE ''Load'' = ?
-`, "''", "`", -1), "foo", "bar")
+LIMIT ?;
+`, "''", "`", -1), "foo", "bar", int64(0))
+}
+
+func LimitPanicStatement() {
+	joinedTable := table1.INNER_JOIN(table2, table1Col1.EQ(table2Col3))
+	joinedTable.UPDATE(table1ColInt).
+		SET(1).
+		WHERE(table1ColInt.GT_EQ(Int(33))).
+		LIMIT(5)
+}
+
+func TestUpdateWithMultiTableAndLimit(t *testing.T) {
+	assertPanicErr(t, func() { LimitPanicStatement() }, "jet: MySQL does not support LIMIT with multi-table UPDATE statements")
 }
 
 func TestInvalidInputs(t *testing.T) {

tests/mysql/update_test.go

@@ -2,10 +2,11 @@ package mysql
 
 import (
 	"context"
-	"github.com/go-jet/jet/v2/qrm"
 	"testing"
 	"time"
 
+	"github.com/go-jet/jet/v2/qrm"
+
 	"github.com/stretchr/testify/require"
 
 	"github.com/go-jet/jet/v2/internal/testutils"
@@ -285,3 +286,56 @@ WHERE link.name = 'Bing';
 		require.NoError(t, err)
 	})
 }
+
+func TestUpdateWithLimit(t *testing.T) {
+	t.Run("single table update with limit", func(t *testing.T) {
+		stmt := Link.
+			UPDATE(Link.Name).
+			SET(String("Updated Link")).
+			WHERE(Link.Name.NOT_EQ(String(""))).
+			LIMIT(2)
+
+		testutils.AssertDebugStatementSql(t, stmt, `
+UPDATE test_sample.link
+SET name = 'Updated Link'
+WHERE link.name != ''
+LIMIT 2;
+`)
+
+		testutils.ExecuteInTxAndRollback(t, db, func(tx qrm.DB) {
+			// Execute update
+			testutils.AssertExec(t, stmt, tx)
+			requireLogged(t, stmt)
+
+			// Verify only 2 rows were updated
+			var updatedLinks []model.Link
+			err := Link.
+				SELECT(Link.AllColumns).
+				WHERE(Link.Name.EQ(String("Updated Link"))).
+				Query(tx, &updatedLinks)
+
+			require.NoError(t, err)
+			require.Equal(t, 2, len(updatedLinks))
+		})
+	})
+
+	t.Run("multi-table update with limit should panic", func(t *testing.T) {
+		defer func() {
+			r := recover()
+			require.NotNil(t, r)
+			require.Equal(t, "jet: MySQL does not support LIMIT with multi-table UPDATE statements", r)
+		}()
+
+		joinedTable := Link.
+			INNER_JOIN(Link2, Link.Name.EQ(Link2.Name))
+
+		stmt := joinedTable.
+			UPDATE(Link.Name).
+			SET(String("Updated Link")).
+			WHERE(Link.Name.NOT_EQ(String(""))).
+			LIMIT(2)
+
+		// Statement construction itself should panic
+		_ = stmt
+	})
+}