Sqlite 简明教程
SQLite - AUTOINCREMENT
SQLite AUTOINCREMENT 是一个用于自动递增表中字段值的关键。我们可以在创建带特定列名称的表来自动递增时通过使用 AUTOINCREMENT 关键字自动递增字段值。
关键字 AUTOINCREMENT 只能与 INTEGER 字段一起使用。
Syntax
AUTOINCREMENT 关键字的基本用法如下:
CREATE TABLE table_name(
column1 INTEGER AUTOINCREMENT,
column2 datatype,
column3 datatype,
.....
columnN datatype,
);
Example
考虑创建如下 COMPANY 表:
sqlite> CREATE TABLE COMPANY(
ID INTEGER PRIMARY KEY AUTOINCREMENT,
NAME TEXT NOT NULL,
AGE INT NOT NULL,
ADDRESS CHAR(50),
SALARY REAL
);
现在,向 COMPANY 表中插入以下记录:
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ( 'Paul', 32, 'California', 20000.00 );
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ('Allen', 25, 'Texas', 15000.00 );
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ('Teddy', 23, 'Norway', 20000.00 );
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ( 'Mark', 25, 'Rich-Mond ', 65000.00 );
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ( 'David', 27, 'Texas', 85000.00 );
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ( 'Kim', 22, 'South-Hall', 45000.00 );
INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)
VALUES ( 'James', 24, 'Houston', 10000.00 );
这将在 COMPANY 表中插入 7 个元组,而 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