常用数据库的自增字段创建方法汇总_DB2_Oracle_MySQL_PostgreSQL_SQL Server_Sybase

DB2




CREATE TABLE T1


(


id INTEGER NOT NULL GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1 MINVALUE 1 NO MAXVALUE NO CYCLE NO CACHE ORDER ),


...


);

Oracle（需要创建一个SEQUENCE和一个TRIGGER）：


CREATE TABLE T1


(


id NUMBER(10,0) NOT NULL,


...


);


CREATE SEQUENCE T1_ID_SEQ INCREMENT BY 1 START WITH 1 NOMAXVALUE NOCYCLE CACHE 100 ORDER;


CREATE OR REPLACE TRIGGER INSERT_T1_ID


BEFORE INSERT ON T1


REFERENCING NEW AS new OLD AS old


FOR EACH ROW


BEGIN


SELECT T1_ID_SEQ.NEXTVAL INTO :new.id FROM DUAL;


END;


/

MySQL



CREATE TABLE T1


(


id INT NOT NULL AUTO_INCREMENT,


...


);

PostgreSQL



CREATE TABLE T1


(


id SERIAL NOT NULL,


...


);

SQL Server


CREATE TABLE T1


(


id INT NOT NULL IDENTITY,


...


);

Sybase


CREATE TABLE T1


(


id INT NOT NULL IDENTITY,


...


);