MySQL存储过程：表名为变量

如果一个存储过程的变化的部分只有表名的部分，我们可以给存储过程传入这个表名。这就需要我们承接一下传入的参数，然后使用PREPARE了，关于PREPARE，需要参考官方文档来解释一下，这里先贴上解决问题的代码：

DELIMITER $$USE `reptail`$$DROP PROCEDURE IF EXISTS `updateTest`$$CREATE DEFINER=`root`@`localhost` PROCEDURE `updateTest`(IN table_name VARCHAR(50))BEGIN    SET @tbl_name=CONCAT("",table_name);    SET @statement = CONCAT("UPDATE ",@tbl_name," AS c,`x1` AS b SET c.`hello` = b.`world` WHERE c.`id` = b.`uuid`; ");    PREPARE stmt FROM @statement;    EXECUTE stmt;    SET @statement = CONCAT("UPDATE ",@tbl_name," AS c,`x2` AS b SET c.`hello` = b.`world` WHERE c.`id` = b.`uuid`; ");    PREPARE stmt FROM @statement;    EXECUTE stmt;    SET @statement = CONCAT("UPDATE ",@tbl_name," AS c,`x3` AS b SET c.`hello` = b.`world` WHERE c.`id` = b.`uuid`; ");    PREPARE stmt FROM @statement;    EXECUTE stmt;    SET @statement = CONCAT("UPDATE ",@tbl_name," AS c,`x4` AS b SET c.`hello` = b.`world` WHERE c.`id` = b.`uuid`; ");    PREPARE stmt FROM @statement;    EXECUTE stmt;    SET @statement = CONCAT("UPDATE ",@tbl_name," AS c,`x5` AS b SET c.`hello` = b.`world` WHERE c.`id` = b.`uuid`; ");    END$$DELIMITER ;

问题解决了，那么，何为PREPARE呢？时至2017年8月24日20:11:48，官方的手册的解释是：

The PREPARE statement prepares a SQL statement and assigns it a name, stmt_name, by which to refer to the statement later. The prepared statement is executed withEXECUTE and released with DEALLOCATE PREPARE. 

翻译为中文的大概意思就是：

PREPARE语句准备一个SQL的statement，并且，它会给这个statement一个名字以便我们之后引用。我们可以使用EXECUTE语句执行这个准备好的statement，也可以使用DEALLOCATE PREPARE来释放掉它。

祝福大家编程顺利，没有bug~

参考：
mysql存储过程中用变量做表名
MYSQL存储过程中 表名 使用变量
MySQL :: MySQL 5.7 Reference Manual :: 13.5.1 PREPARE Syntax