fix(kingbase): report compatibility identifier quote

agents/drivers/kingbase-go/kingbase_metadata.go

@@ -152,6 +152,15 @@ func mysqlSQLModeExists(db *sql.DB) bool {
 	return db.QueryRow("SELECT 1 FROM sys_catalog.sys_settings WHERE LOWER(name) = 'sql_mode'").Scan(&value) == nil
 }
 
+func (s *server) identifierQuote() string {
+	// Kingbase MySQL compatibility mode follows MySQL identifier quoting;
+	// other modes retain the PostgreSQL-compatible double quote.
+	if s.mode.mysqlCompat {
+		return "`"
+	}
+	return `"`
+}
+
 func (s *server) connectionInfo() (map[string]any, error) {
 	db, err := s.requireDB()
 	if err != nil {
@@ -164,7 +173,7 @@ func (s *server) connectionInfo() (map[string]any, error) {
 	}
 	return map[string]any{
 		"database": database, "username": username, "version": version, "schema": schema,
-		"mysql_compat_mode": s.mode.mysqlCompat,
+		"mysql_compat_mode": s.mode.mysqlCompat, "identifierQuote": s.identifierQuote(),
 	}, nil
 }
 

agents/drivers/kingbase-go/main_test.go

@@ -163,6 +163,11 @@ func (connection *modeDetectionConn) QueryContext(_ context.Context, query strin
 	connection.state.mu.Unlock()
 
 	switch {
+	case strings.Contains(query, "SELECT current_database()"):
+		return &valueRows{
+			columns: []string{"current_database", "current_user", "version", "current_schema"},
+			rows:    [][]driver.Value{{"test", "system", "KingbaseES", "public"}},
+		}, nil
 	case strings.Contains(query, "LOWER(name) = 'database_mode'"):
 		if connection.state.databaseErr != nil {
 			return nil, connection.state.databaseErr
@@ -470,6 +475,32 @@ func TestDetectMySQLCompatModePrefersDatabaseModeOverSQLModePresence(t *testing.
 	}
 }
 
+func TestConnectionInfoReportsCompatibilityIdentifierQuote(t *testing.T) {
+	for _, testCase := range []struct {
+		name        string
+		mysqlCompat bool
+		expected    string
+	}{
+		{name: "postgres compatible", expected: `"`},
+		{name: "mysql compatible", mysqlCompat: true, expected: "`"},
+	} {
+		t.Run(testCase.name, func(t *testing.T) {
+			db := openModeDetectionDB(t, &modeDetectionDriverState{})
+			server := newServer()
+			server.db = db
+			server.mode.mysqlCompat = testCase.mysqlCompat
+
+			info, err := server.connectionInfo()
+			if err != nil {
+				t.Fatal(err)
+			}
+			if info["identifierQuote"] != testCase.expected {
+				t.Fatalf("unexpected identifier quote: %#v", info["identifierQuote"])
+			}
+		})
+	}
+}
+
 func TestDetectMySQLCompatModeFallsBackToSQLModeWhenDatabaseModeMissing(t *testing.T) {
 	state := &modeDetectionDriverState{sqlModeExists: true}
 	db := openModeDetectionDB(t, state)

crates/dbx-core/src/sql_dialect/tests.rs

@@ -316,7 +316,7 @@ fn builds_table_data_where_and_schema_queries() {
         build_table_data_select_sql(TableDataSelectSqlOptions {
             database_type: Some(DatabaseType::Kingbase),
             identifier_quote: Some("`".to_string()),
-            schema: Some("cqbq_ls".to_string()),
+            schema: Some("nacos-v3".to_string()),
             table_name: "actionlogs".to_string(),
             table_type: None,
             primary_keys: Vec::new(),
@@ -329,7 +329,7 @@ fn builds_table_data_where_and_schema_queries() {
             include_row_id: false,
             ..Default::default()
         }),
-        "SELECT * FROM `cqbq_ls`.`actionlogs` LIMIT 100;"
+        "SELECT * FROM `nacos-v3`.`actionlogs` LIMIT 100;"
     );
     assert_eq!(
         build_table_data_select_sql(TableDataSelectSqlOptions {