MySQL的異常處理分析如下：
標(biāo)準(zhǔn)格式
DECLARE handler_type HANDLER FOR condition_value[,...] statementhandler_type: CONTINUE | EXIT | UNDO --這個(gè)暫時(shí)不支持condition_value: SQLSTATE [VALUE] sqlstate_value | condition_name | SQLWARNING | NOT FOUND | SQLEXCEPTION | mysql_error_codecondition_value細(xì)節(jié)
1、常用MYSQL ERROR CODE 列表
http://dev.mysql.com/doc/refman/5.0/en/error-messages-server.html
更多錯(cuò)誤列表見MySQL安裝路徑下
比如我的/usr/local/mysql/share/mysql/errmsg.txt
說明一下：SQLSTATE [VALUE] sqlstate_value這種格式是專門為ANSI SQL 和 ODBC以及其他的標(biāo)準(zhǔn).
并不是所有的MySQL ERROR CODE 都映射到SQLSTATE。
2、如果你不想插ERROR CODE的話，就用速記條件來(lái)代替
SQLWARNING 代表所有以01開頭的錯(cuò)誤代碼
NOT FOUND 代表所有以02開頭的錯(cuò)誤代碼，當(dāng)然也可以代表一個(gè)游標(biāo)到達(dá)數(shù)據(jù)集的末尾。
SQLEXCEPTION 代表除了SQLWARNING和NOT FOUND 的所有錯(cuò)誤代碼
3、我們現(xiàn)在就用手冊(cè)上的例子
CREATE TABLE t (s1 int,primary key (s1));mysql> use t_girlDatabase changedmysql> CREATE TABLE t (s1 int,primary key (s1));Query OK, 0 rows affected (0.00 sec)mysql> mysql> mysql> DELIMITER ||mysql> CREATE PROCEDURE handlerdemo () -> BEGIN -> DECLARE EXIT HANDLER FOR SQLSTATE '23000' BEGIN END; -- 遇到重復(fù)鍵值就退出 -> SET @x = 1; -> INSERT INTO t VALUES (1); -> SET @x = 2; -> INSERT INTO t VALUES (1); -> SET @x = 3; -> END||Query OK, 0 rows affected (0.00 sec)mysql> DELIMITER ;mysql> call handlerdemo();Query OK, 0 rows affected (0.00 sec)mysql> select @x;+------+| @x |+------+| 2 | +------+1 row in set (0.00 sec)mysql> call handlerdemo();Query OK, 0 rows affected (0.00 sec)mysql> select @x;+------+| @x |+------+| 1 | +------+1 row in set (0.00 sec)mysql>
現(xiàn)在來(lái)看一下遇到錯(cuò)誤繼續(xù)的情況
mysql> truncate table t;Query OK, 0 rows affected (0.01 sec)mysql> DELIMITER $$mysql> DROP PROCEDURE IF EXISTS `t_girl`.`handlerdemo`$$Query OK, 0 rows affected (0.00 sec)mysql> CREATE DEFINER=`root`@`localhost` PROCEDURE `handlerdemo`() -> BEGIN -> DECLARE CONTINUE HANDLER FOR SQLSTATE '23000' BEGIN END; -> SET @x = 1; -> INSERT INTO t VALUES (1); -> SET @x = 2; -> INSERT INTO t VALUES (1); -> SET @x = 3; -> END$$Query OK, 0 rows affected (0.01 sec)mysql> DELIMITER ;mysql> call handlerdemo();Query OK, 0 rows affected (0.00 sec)mysql> select @x;+------+| @x |+------+| 3 | +------+1 row in set (0.00 sec)mysql> call handlerdemo();Query OK, 0 rows affected (0.00 sec)mysql> select @x;+------+| @x |+------+| 3 | +------+1 row in set (0.00 sec)mysql>
可以看到，始終執(zhí)行到最后。
當(dāng)然，上面的SQLSTATE '23000'可以替換為1062
我們來(lái)看一下警告。
mysql> alter table t add s2 int not null;Query OK, 0 rows affected (0.01 sec)Records: 0 Duplicates: 0 Warnings: 0
此列沒有默認(rèn)值，插入的時(shí)候會(huì)出現(xiàn)警告或者1364錯(cuò)誤提示。
mysql> DELIMITER $$mysql> DROP PROCEDURE IF EXISTS `t_girl`.`handlerdemo`$$Query OK, 0 rows affected, 1 warning (0.00 sec)mysql> CREATE DEFINER=`root`@`localhost` PROCEDURE `handlerdemo`() -> BEGIN -> DECLARE CONTINUE HANDLER FOR 1062 BEGIN END; -> DECLARE CONTINUE HANDLER FOR SQLWARNING -> BEGIN -> update t set s2 = 2; -> END; -> DECLARE CONTINUE HANDLER FOR 1364 -> BEGIN -> INSERT INTO t(s1,s2) VALUES (1,3); -> END; -> SET @x = 1; -> INSERT INTO t(s1) VALUES (1); -> SET @x = 2; -> INSERT INTO t(s1) VALUES (1); -> SET @x = 3; -> END$$Query OK, 0 rows affected (0.00 sec)mysql> DELIMITER ;mysql> call handlerdemo();Query OK, 0 rows affected (0.00 sec)mysql> select * from t;+----+----+| s1 | s2 |+----+----+| 1 | 3 | +----+----+1 row in set (0.00 sec)
遇到錯(cuò)誤的時(shí)候插入的新記錄。
mysql> select @x;+------+| @x |+------+| 3 | +------+1 row in set (0.00 sec)
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