sqlite的AUTOINCREMENT是一个关键字,用于表中的字段值自动递增。我们可以自动增加一个字段值使用AUTOINCREMENT关键字带有具体列名创建表时自动递增。
整型字段可以使用关键字AUTOINCREMENT。
语法
AUTOINCREMENT关键字的基本用法如下:
CREATE TABLE table_name( column1 INTEGER AUTOINCREMENT,column2 datatype,column3 datatype,..... columnN datatype,);
例子:
考虑COMPANY表要创建如下:
CREATE TABLE COMPANY( ID INTEGER PRIMARY KEY AUTOINCREMENT,NAME TEXT NOT NULL,AGE INT NOT NULL,ADDRESS CHAR(50),SALARY REAL );
现在,以下记录插入到表 COMPANY:
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY) VALUES ( 'Paul',32,'California',20000.00 );
INSERT INTO COMPANY (NAME,SALARY) VALUES ('Allen',25,'Texas',15000.00 );
INSERT INTO COMPANY (NAME,SALARY) VALUES ('Teddy',23,'Norway',SALARY) VALUES ( 'Mark','Rich-Mond ',65000.00 );
INSERT INTO COMPANY (NAME,SALARY) VALUES ( 'David',27,85000.00 );
INSERT INTO COMPANY (NAME,SALARY) VALUES ( 'Kim',22,'South-Hall',45000.00 );
INSERT INTO COMPANY (NAME,SALARY) VALUES ( 'James',24,'Houston',10000.00 );
这将插入到表COMPANY 7个元组,COMPANY将有以下记录:
ID NAME AGE ADDRESS SALARY
---------- ---------- ---------- ---------- ----------
1 Paul 32 California 20000.0
2 Allen 25 Texas 15000.0
3 Teddy 23 Norway 20000.0
4 Mark 25 Rich-Mond 65000.0
5 David 27 Texas 85000.0
6 Kim 22 South-Hall 45000.0
7 James 24 Houston 10000.0