Support new synatx CREATE TABLE [IF NOT EXISTS] [db_name].table_name AS [db_name2].table_name2; to create a new table from existed table with same table schema. ISSUE: #4355
Support new synatx CREATE TABLE [IF NOT EXISTS] [db_name].table_name AS [db_name2].table_name2; to create a new table from existed table with same table schema. ISSUE: #4355