Question

我正在尝试将此查询转换为MySQL函数

SET @v1 := (
SELECT  count(id) as count
    FROM  article_category
    where  (title like "About Usd")
        or (title like "About Usd-%"  and  title regexp '[0-9]$')
           ); 
INSERT  INTO `article_category`
    (`title`,`meta_data`,`meta_description`)
    VALUES
    ( IF(@v1 <= 0, "About Usd", CONCAT("About Usd","-",@v1) ), 
      "ddddD",
      "ddddddd" );

此函数应返回下一个可用名称，以便我可以直接在insert语句中使用它：

CREATE FUNCTION `get_next_unique_name`(tabel nvarchar(255),naem nvarchar(255)) RETURNS NVARCHAR(255)
    DETERMINISTIC
BEGIN
 SET @dd = SELECT count(id) as count FROM tabel where (title like naem) or (title like (naem+'-%') and title regexp '[0-9]$');
 RETURN (naem+'-'+@dd);
END

Answer 1

您必须在SET @dd行上收到错误。

您不能通过指定语句将值设置为任何变量您必须使用SELECT .... INTO ...语法为变量设置值。

您的代码中还有其他几个错误按照以下建议更改它们：

CREATE 
    FUNCTION `get_next_unique_name`( tabel nvarchar(255), naem nvarchar(255) )
    RETURNS NVARCHAR(255)
    DETERMINISTIC
BEGIN
    DECLARE _count INT DEFAULT 0;
    SELECT count(id) INTO _count 
      FROM tabel 
     WHERE ( title LIKE naem ) 
        OR ( title LIKE CONCAT( naem, '-%' ) AND title REGEXP '[0-9]$' );

    RETURN CONCAT( naem, '-', _count );
END;

MySQL函数，参数语法错误

1 个答案: