为什么我收到此错误？
CREATE DEFINER=`root`@`localhost` PROCEDURE `selectrecords`(tablename varchar(50))
begin
set @table_name=tablename;
set @sql_text=concat('Select * from @table_name');
prepare statement from @sql_text;
execute statement;
deallocate prepare statement;
end
错误：
....to use near '@table_name' at line 1
我的代码是正确的,但我不明白为什么….
最佳答案
我想你的意思是,
CREATE PROCEDURE `selectrecords`(tablename varchar(50))
begin
set @sql_text = concat('Select * from ',tablename);
prepare statement from @sql_text;
execute statement;
deallocate prepare statement;
end
即使在动态sql中,也不能参数化表名和列名,因此您唯一的选择是与字符串连接.只有值可以放在占位符中.
更新1
CREATE PROCEDURE `selectrecords`(tablename varchar(50))
begin
set @val = idnumber;
set @sql_text = concat('Select * from ',tablename,' WHERE id = ?');
prepare statement from @sql_text;
execute statement USING @val;
deallocate prepare statement;
end