private Pair<String, String> getDatabaseAndTableName(String tableName) {
        String databaseName = "default";
        if (tableName.contains(POINT)) {
            String[] tableNameArray = tableName.split("\\.");
            databaseName = tableNameArray[0];
            tableName = tableNameArray[1];
        } else {
            LOG.warn("TableName doesn't include database name, so using default as database name");
        }
        return Pair.of(databaseName, tableName);
    }
mysql throw exception "Table default.test_user doesn't exist". But jdbc-url have database name.
So we specify database when exec query. This method parse tableName to database and table.
@param tableName include database.table
@return pair left is database, right is table
inlong-sort/sort-flink/sort-flink-v1.15/sort-connectors/jdbc/src/main/java/org/apache/inlong/sort/jdbc/dialect/jdbc/JdbcDialect.java