VOLATILE

The table-specific keyword VOLATILE is provided in the input file, but the keyword is not supported by GaussDB(DWS). The tool replaces it with the LOCAL TEMPORARY keyword during the migration process. Volatile tables are migrated as local temporary or unlogged based on the config input.

Input: CREATE VOLATILE TABLE

   
         CREATE VOLATILE TABLE T1 (c1 int ,c2 int);

Output:

   
        CREATE
    LOCAL TEMPORARY TABLE
    T1 (
         c1 INTEGER
        ,c2 INTEGER
       )
;

Input: CREATE VOLATILE TABLE AS WITH DATA (session_mode=Teradata)

If the source table has a PRIMARY KEY or a UNIQUE CONSTRAINT, then it will not contain any duplicate records. In this case, the MINUS operator is not required or added to remove duplicate records.

   
        CREATE VOLATILE TABLE tabV1 (
        C1 INTEGER DEFAULT 99
       ,C2 INTEGER
       ,C3 INTEGER
       ,C4 NUMERIC (20,0) DEFAULT NULL (BIGINT)
       ,CONSTRAINT XX1 PRIMARY KEY ( C1, C2 )
       ) PRIMARY INDEX (C1, C3 );

CREATE TABLE tabV2 AS tabV1 WITH DATA PRIMARY INDEX (C1)
             ON COMMIT PRESERVE ROWS;

Output:

   
        CREATE LOCAL TEMPORARY TABLE tabV1 (
        C1 INTEGER DEFAULT 99
       ,C2 INTEGER
       ,C3 INTEGER
       ,C4 NUMERIC (20,0) DEFAULT CAST( NULL AS BIGINT )
       ,CONSTRAINT XX1 PRIMARY KEY ( C1, C2 )
       ) DISTRIBUTE BY HASH (C1);

BEGIN 
    CREATE TABLE tabV2 (
               LIKE tabV1 INCLUDING ALL EXCLUDING PARTITION EXCLUDING RELOPTIONS EXCLUDING DISTRIBUTION
                       ) DISTRIBUTE BY HASH (C1);
    INSERT INTO tabV2 SELECT * FROM tabV1;
END
;
/