如果你不想使用mysql的自動(dòng)遞增，但又想實(shí)現(xiàn)主鍵序列號(hào)的功能，可以使用下面的方法，通過(guò)函數(shù)用一張表去維護(hù)生成多個(gè)表的序列號(hào)，簡(jiǎn)單又實(shí)用
1.創(chuàng)建生成多個(gè)表的序列號(hào)的數(shù)據(jù)維護(hù)表
CREATE TABLE seq (
name varchar(20) NOT NULL,
val int(10) UNSIGNED NOT NULL,
PRIMARY KEY (name)
) ENGINE=MyISAM DEFAULT CHARSET=UTF-8
2.插入幾條初始化數(shù)據(jù)
INSERT INTO seq VALUES('one',100);
INSERT INTO seq VALUES('two',1000);
3.創(chuàng)建函數(shù)以生成序列號(hào)
CREATE FUNCTION seq(seq_name char (20)) returns int
begin
UPDATE seq SET val=last_insert_id(val+1) WHERE name=seq_name;
RETURN last_insert_id();
end
4.測(cè)試
-
mysql> SELECT seq('one'),seq('two'),seq('one'),seq('one');
-
+------------+------------+------------+------------+
-
| seq('one') | seq('two') | seq('one') | seq('one') |
-
+------------+------------+------------+------------+
-
| 102 | 1002 | 103 | 104 |
-
+------------+------------+------------+------------+
-
1 row IN SET (0.00 sec)
整理 www.aygfsteel.com/Good-Game