MySql游标遍历的记录数不完整

在项目中使用MySql存储过程中，使用游标遍历数据，发现定义游标的查询语句有8条记录，循环遍历的时候却只循环了一次；

查看MySql官方文档才发现，不仅到达游标结尾会有NOT FOUND condition发生，select … into …，没有查到数据，同样也会有NOT FOUND condition发生，因此在遍历游标循环里使用select … into … 以后，一定要把循环标志位置位；MySql官方文档说明如下：

NOT FOUND: Shorthand for the class of SQLSTATE values that begin with ‘02’. This is relevant within the context of cursors and is used to control what happens when a cursor reaches the end of a data set. If no more rows are available, a No Data condition occurs with SQLSTATE value ‘02000’. To detect this condition, you can set up a handler for it or for a NOT FOUND condition.

The NOT FOUND condition also occurs for SELECT … INTO var_list statements that retrieve no rows.