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HomeDatabaseMysql Tutorial浅析常用数据库的自增字段创建方法汇总

浅析常用数据库的自增字段创建方法汇总

Jun 07, 2016 pm 04:19 PM
createFieldCommonly useddatabasemethodSummaryself-increasing

本篇文章是对常用数据库的自增字段创建方法进行了全面的汇总介绍,需要的朋友参考下 DB2 复制代码 代码如下: 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

本篇文章是对常用数据库的自增字段创建方法进行了全面的汇总介绍,,需要的朋友参考下

 

DB2

复制代码 代码如下:


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):

复制代码 代码如下:


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

复制代码 代码如下:


CREATE TABLE T1
(
   id INT NOT NULL AUTO_INCREMENT,
   ...
);


PostgreSQL

复制代码 代码如下:


CREATE TABLE T1
(
   id SERIAL NOT NULL,
   ...
);


SQL Server

复制代码 代码如下:


CREATE TABLE T1
(
   id INT NOT NULL IDENTITY,
   ...
);


Sybase

复制代码 代码如下:


CREATE TABLE T1
(
   id INT NOT NULL IDENTITY,
   ...
);

Statement
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