Transaction Management and Database Management

DSC will perform adaptation based on GaussDB features during MySQL transaction statement migration.

Input

## Each statement applies only to the next single transaction performed within the session. 
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET TRANSACTION ISOLATION LEVEL REPEATABLE READ;
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
SET TRANSACTION READ ONLY;
SET TRANSACTION READ WRITE;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED,READ ONLY;
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE,READ WRITE;
## Each statement (with the SESSION keyword) applies to all subsequent transactions performed within the current session. 
START TRANSACTION;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
commit ;

Output

-- Each statement applies only to the next single transaction performed within the session. 
SET LOCAL TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET LOCAL TRANSACTION ISOLATION LEVEL REPEATABLE READ;
SET LOCAL TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
SET LOCAL TRANSACTION ISOLATION LEVEL SERIALIZABLE;
SET LOCAL TRANSACTION READ ONLY;
SET LOCAL TRANSACTION READ WRITE;
SET LOCAL TRANSACTION ISOLATION LEVEL READ COMMITTED READ ONLY;
SET LOCAL TRANSACTION ISOLATION LEVEL SERIALIZABLE READ WRITE;
-- Each statement (with the SESSIONkeyword) applies to all subsequent transactions performed within the current session. 
START TRANSACTION;
SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL SERIALIZABLE;
SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL SERIALIZABLE;
COMMIT WORK;

DSC will perform adaptation based on GaussDB features during the migration of MySQL table locking statements which are used in transaction processing.

Input

## A.
START TRANSACTION;
LOCK TABLES `mt`.`runoob_tbl` WRITE,`mt`.`runoob_tb2` READ;
commit;

## B.
START TRANSACTION;
LOCK TABLES `mt`.`runoob_tbl` WRITE;
commit;

## C.
START TRANSACTION;
LOCK TABLES `mt`.`runoob_tbl` READ,`mt`.`runoob_tbl` AS t1 READ;
commit;

Output

-- A.
START TRANSACTION;
LOCK TABLE "mt"."runoob_tbl" IN ACCESS EXCLUSIVE MODE;
LOCK TABLE "mt"."runoob_tb2" IN ACCESS SHARE MODE;
COMMIT WORK;

-- B.
START TRANSACTION;
LOCK TABLE "mt"."runoob_tbl" IN ACCESS EXCLUSIVE MODE;
COMMIT WORK;

-- C.
START TRANSACTION;
LOCK TABLE "mt"."runoob_tbl" IN ACCESS SHARE MODE;
COMMIT WORK;

DSC will replace MySQL SET CHARACTER SET with SET SESSION NAMES during migration. The following table lists character set mapping.

Input

SET CHARACTER SET 'ASCII';
SET CHARACTER SET 'BIG5';
SET CHARACTER SET 'CP1250';
SET CHARACTER SET 'CP1251';
SET CHARACTER SET 'CP1256';
SET CHARACTER SET 'CP1257';
SET CHARACTER SET 'CP932';
SET CHARACTER SET 'EUCJPMS';
SET CHARACTER SET 'EUCKR';
SET CHARACTER SET 'GB2312';
SET CHARACTER SET 'GBK';
SET CHARACTER SET 'GREEK';
SET CHARACTER SET 'HEBREW';
SET CHARACTER SET 'KOI8R';
SET CHARACTER SET 'KOI8U';
SET CHARACTER SET 'LATIN1';
SET CHARACTER SET 'LATIN2';
SET CHARACTER SET 'LATIN5';
SET CHARACTER SET 'LATIN7';
SET CHARACTER SET 'SJIS';
SET CHARACTER SET 'SWE7';
SET CHARACTER SET 'TIS620';
SET CHARACTER SET 'UTF8';
SET CHARACTER SET 'UTF8MB4';
## MySQL does not support SET CHARACTER SET 'UCS2';. 
## MySQL does not support SET CHARACTER SET 'UTF16';. 
## MySQL does not support SET CHARACTER SET 'UTF16LE';. 
## MySQL does not support SET CHARACTER SET 'UTF32';.

Output

SET SESSION NAMES 'SQL_ASCII';
SET SESSION NAMES 'BIG5';
SET SESSION NAMES 'WIN1250';
SET SESSION NAMES 'WIN1251';
SET SESSION NAMES 'WIN1256';
SET SESSION NAMES 'WIN1257';
SET SESSION NAMES 'SJIS';
SET SESSION NAMES 'EUC_JP';
SET SESSION NAMES 'EUC_KR';
SET SESSION NAMES 'GB18030';
SET SESSION NAMES 'GBK';
SET SESSION NAMES 'ISO_8859_7';
SET SESSION NAMES 'ISO_8859_8';
SET SESSION NAMES 'KOI8R';
SET SESSION NAMES 'KOI8U';
SET SESSION NAMES 'LATIN1';
SET SESSION NAMES 'LATIN2';
SET SESSION NAMES 'LATIN5';
SET SESSION NAMES 'LATIN7';
SET SESSION NAMES 'SJIS';
SET SESSION NAMES 'UTF8';
SET SESSION NAMES 'WIN874';
SET SESSION NAMES 'UTF8';
SET SESSION NAMES 'UTF8';
-- MySQL does not support SET CHARACTER SET 'UCS2';. 
-- MySQL does not support SET CHARACTER SET 'UTF16';. 
-- MySQL does not support SET CHARACTER SET 'UTF16LE';. 
-- MySQL does not support SET CHARACTER SET 'UTF32';.