fix(pgsql,gaussdb): translate LockShared() syntax in DoFilter

LockShared() generates "LOCK IN SHARE MODE" which is MySQL-only syntax.
Add DoFilter translation to "FOR SHARE" for PgSQL and GaussDB drivers,
consistent with existing dialect translations (LIMIT, INSERT IGNORE).

Tests now use LockShared() directly instead of Lock("FOR SHARE") workaround.

Author: lingcoder

contrib/drivers/gaussdb/gaussdb_do_filter.go

@@ -56,6 +56,11 @@ func (d *Driver) DoFilter(
 		newSql = "INSERT" + newSql[len(gdb.InsertOperationIgnore):]
 	}
 
+	// Translate MySQL shared lock syntax to GaussDB (PostgreSQL-compatible) syntax.
+	// LockShared() generates "LOCK IN SHARE MODE" which is MySQL-only;
+	// GaussDB uses "FOR SHARE" for the same semantics.
+	newSql = gstr.Replace(newSql, "LOCK IN SHARE MODE", "FOR SHARE")
+
 	newArgs = args
 
 	return d.Core.DoFilter(ctx, link, newSql, newArgs)

contrib/drivers/pgsql/pgsql_do_filter.go

@@ -52,6 +52,11 @@ func (d *Driver) DoFilter(
 		newSql = "INSERT" + newSql[len(gdb.InsertOperationIgnore):] + " ON CONFLICT DO NOTHING"
 	}
 
+	// Translate MySQL shared lock syntax to PostgreSQL syntax.
+	// LockShared() generates "LOCK IN SHARE MODE" which is MySQL-only;
+	// PostgreSQL uses "FOR SHARE" for the same semantics.
+	newSql = gstr.Replace(newSql, "LOCK IN SHARE MODE", "FOR SHARE")
+
 	newArgs = args
 
 	return d.Core.DoFilter(ctx, link, newSql, newArgs)

contrib/drivers/pgsql/pgsql_z_unit_feature_lock_test.go

@@ -28,7 +28,7 @@ func Test_Model_Lock(t *testing.T) {
 		t.Assert(one["id"], 1)
 
 		// Test Lock with FOR SHARE (PgSQL equivalent of MySQL's LOCK IN SHARE MODE)
-		one, err = db.Model(table).Lock("FOR SHARE").Where("id", 3).One()
+		one, err = db.Model(table).Lock(gdb.LockForShare).Where("id", 3).One()
 		t.AssertNil(err)
 		t.Assert(one["id"], 3)
 
@@ -61,20 +61,19 @@ func Test_Model_LockUpdate(t *testing.T) {
 }
 
 // Test_Model_LockShared tests the LockShared convenience method.
-// PgSQL: LockShared() generates "LOCK IN SHARE MODE" which is MySQL-only.
-// Use Lock("FOR SHARE") instead for PgSQL equivalent.
+// PgSQL DoFilter translates "LOCK IN SHARE MODE" to "FOR SHARE" automatically.
 func Test_Model_LockShared(t *testing.T) {
 	table := createInitTable()
 	defer dropTable(table)
 
 	gtest.C(t, func(t *gtest.T) {
-		// Test Lock("FOR SHARE") basic usage (PgSQL equivalent of LockShared)
-		one, err := db.Model(table).Lock("FOR SHARE").Where("id", 1).One()
+		// Test LockShared basic usage
+		one, err := db.Model(table).LockShared().Where("id", 1).One()
 		t.AssertNil(err)
 		t.Assert(one["id"], 1)
 
-		// Test Lock("FOR SHARE") with All()
-		all, err := db.Model(table).Lock("FOR SHARE").Where("id<=?", 5).Order("id").All()
+		// Test LockShared with All()
+		all, err := db.Model(table).LockShared().Where("id<=?", 5).Order("id").All()
 		t.AssertNil(err)
 		t.Assert(len(all), 5)
 		t.Assert(all[0]["id"], 1)
@@ -186,7 +185,7 @@ func Test_Model_Lock_ChainedMethods(t *testing.T) {
 		t.Assert(one["passport"], "user_1")
 
 		// Lock with Order and Limit
-		all, err := db.Model(table).Lock("FOR SHARE").Where("id>?", 5).Order("id desc").Limit(3).All()
+		all, err := db.Model(table).LockShared().Where("id>?", 5).Order("id desc").Limit(3).All()
 		t.AssertNil(err)
 		t.Assert(len(all), 3)
 		t.Assert(all[0]["id"], 10)