常用数据库的自增字段创建方法汇总

DB2

CREATE TABLE T1
(
id INTEGER NOT NULL GENERATEDALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1 MINVALUE 1 NOMAXVALUENOCYCLENOCACHE ORDER ),
...
);

Oracle（需要创建一个SEQUENCE和一个TRIGGER）：

CREATETABLET1
(
idNUMBER(10,0)NOTNULL,
...
);
CREATESEQUENCET1_ID_SEQINCREMENTBY1STARTWITH1NOMAXVALUENOCYCLECACHE100ORDER;
CREATEORREPLACETRIGGERINSERT_T1_ID
BEFOREINSERTONT1
REFERENCINGNEWASnewOLDASold
FOREACHROW
BEGIN
SELECTT1_ID_SEQ.NEXTVALINTO:new.idFROMDUAL;
END;
/

MySQL

CREATETABLET1
(
idINTNOTNULLAUTO_INCREMENT,
...
);

PostgreSQL

CREATETABLET1
(
idSERIALNOTNULL,
...
);

SQL Server

CREATETABLET1
(
idINTNOTNULLIDENTITY,
...
);

Sybase

CREATETABLET1
(
idINTNOTNULLIDENTITY,
...
);