MySQL 错误处理例子[译]

from http://www.devshed.com/c/a/MySQL/Error-Handling-Examples/ 
Error Handler Examples 
Here are some examples of handler declarations: 
If any error condition arises (other than a NOT FOUND ), continue execution after setting l_error=1 : 
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION 
SET l_error=1; 
If any error condition arises (other than a NOT FOUND ), exit the current block or stored program after issuing a ROLLBACK statement and issuing an error message: 
DECLARE EXIT HANDLER FOR SQLEXCEPTION 
BEGIN 
ROLLBACK; 
SELECT 'Error occurred – terminating'; 
END; 
If MySQL error 1062 (duplicate key value) is encountered, continue execution after executing the SELECT statement (which generates a message for the calling program): 
DECLARE CONTINUE HANDER FOR 106 2 
SELECT 'Duplicate key in index'; 
If SQLSTATE 23000 (duplicate key value) is encountered, continue execution after executing the SELECT statement (which generates a message for the calling program): 
DECLARE CONTINUE HANDER FOR SQLSTATE '23000' 
SELECT 'Duplicate key in index'; 
When a cursor fetch or SQL retrieves no values, continue execution after setting l_done=1 : 
DECLARE CONTINUE HANDLER FOR NOT 
FOUND 
SET l_done=1; 
Same as the previous example, except specified using a SQLSTATE variable rather than a named condition: 
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000 ' 
SET l_done=1; 
Same as the previous two examples, except specified using a MySQL error code variable rather than a named condition or SQLSTATE variable: 
DECLARE CONTINUE HANDLER FOR 1329 
SET l_done=1; 

错误处理例子 
有几种错误处理的声明形式： 
§ 如果任何错误（不是 NOT FOUND ） , 设置 l_error 为 1 后继续执行： 
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION 
SET l_error=1; 
§ 如果发生任何错误（不是 NOT FOUND）， 执行 ROLLBACK和产生一条错误消息后退出当前块或存储过程。 
DECLARE EXIT HANDLER FOR SQLEXCEPTION 
BEGIN 
ROLLBACK; 
SELECT 'Error occurred – terminating'; 
END; 
§ 如果 MySQL 1062错误 (重复的健值 )发生，执行 SELECT语句（向调用程序发一条消息）后继续执行 
DECLARE CONTINUE HANDER FOR 106 2 
SELECT 'Duplicate key in index'; 
§ 如果 SQLSTATE 2300错误 (重复的健值 )发生，执行 SELECT语句（向调用程序发一条消息）后继续执行 
DECLARE CONTINUE HANDER FOR SQLSTATE '23000' 
SELECT 'Duplicate key in index'; 
§ 当游标或者 SQL 选择语句没有返回值时，设置 l_done=1 后继续执行 
DECLARE CONTINUE HANDLER FOR NOT 
FOUND 
SET l_done=1; 
§ 此例除了用 SQLSTATE 变量而不是命名条件以外，跟前一个例子一样 
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000 ' 
SET l_done=1; 
§ 此例除了用 MySQL 的错误码变量而不是命名条件或者 SQLSTATE 变量以外，跟前两个例子一样 
DECLARE CONTINUE HANDLER FOR 1329 
SET l_done=1;