SQLite AUTO INCREMENT/自動遞增
SQLite的AUTOINCREMENT是一個關鍵字,用於表中的字段值自動遞增。我們可以自動增加一個字段值使用AUTOINCREMENT關鍵字帶有具體列名創建表時自動遞增。
整型字段可以使用關鍵字AUTOINCREMENT。
語法
AUTOINCREMENT關鍵字的基本用法如下:
CREATE TABLE table_name( column1 INTEGER AUTOINCREMENT, column2 datatype, column3 datatype, ..... columnN datatype, );
例子:
考慮COMPANY表要創建如下:
sqlite> CREATE TABLE COMPANY( ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INT NOT NULL, ADDRESS CHAR(50), SALARY REAL );
現在,以下記錄插入到表 COMPANY:
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 );
這將插入到表COMPANY 7個元組,COMPANY將有以下記錄:
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