mysql 存储过程表名做参数的问题
mysql> create procedure p1 ($table_name varchar(20))
-> begin
-> set @sql=concat('select * from '+$table_name);
-> prepare stmt1 from @sql;
-> execute stmt1;
-> deallocate prepare stmt1;
-> end;
运行时输入表名users提示:1054-Unknown column 'users' in 'field list'
这是怎么回事