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MySql 功能: 更改表名称,以在《选举声明》中使用
原标题:MySql Functions: Convert VARCHAR to actual tablename to use in a SELECT Statement

如何在实际的《选举声明》中使用职能参数

CREATE FUNCTION GetDefaultLangText(tableName VARCHAR(50), fieldName VARCHAR(50)) 
RETURNS VARCHAR(200) DETERMINISTIC
BEGIN  
Select fieldName from tableName
END

它告诉我,这确实没有工作。 姓名当然确实存在,但我真的想要的是,在变量表Name(和外地名称)中拿出实际价值。

问题回答

在MySQL的变数必须用@预先确定,否则它们就被视为原始外地/表名......

SELECT @fieldName FROM @tableName

然而,这 s是允许的。 不能通过变数将外地名称和表名插入查询:。 MySQL 存储程序动态变更表。 因此,改变你的询问,不会解决更大的问题。

Something similar has been posted awhile back: use a variable for table name in mysql sproc

你们可以像:

PREPARE stmt FROM @sqltext; EXECUTE stmt USING @temptable; DEALLOCATE PREPARE stmt;

qltext是一种可以包含质子的扼杀。





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