Question

我想在不使用任何if语句的情况下重写此代码。

有可能吗？

我如何使用案例或其他内容？

IF @BrandFilter = ''
    BEGIN
        SELECT * FROM
        (
            SELECT
                ROW_NUMBER() OVER(ORDER BY  
                CASE WHEN @SortType = '1' THEN mt.Ad END ASC,
                CASE WHEN @SortType = '2' THEN mt.Ad END DESC,
                CASE WHEN @SortType = '3' THEN mt.Fiyat END ASC,
                CASE WHEN @SortType = '4' THEN mt.Fiyat END DESC) AS RowNr, * 
            FROM @MainTable mt
            WHERE mt.Fiyat > @MinPrice AND mt.Fiyat < @MaxPrice     
        ) Result
        WHERE RowNr > ((@PageNr-1) * 10) AND RowNr <= ((@PageNr) * 10)  
    END
ELSE
    BEGIN
        SELECT * FROM
        (
            SELECT
                ROW_NUMBER() OVER(ORDER BY  
                CASE WHEN @SortType = '1' THEN mt.Ad END ASC,
                CASE WHEN @SortType = '2' THEN mt.Ad END DESC,
                CASE WHEN @SortType = '3' THEN mt.Fiyat END ASC,
                CASE WHEN @SortType = '4' THEN mt.Fiyat END DESC) AS RowNr, * 
            FROM @MainTable mt
            WHERE mt.Fiyat > @MinPrice AND mt.Fiyat < @MaxPrice
            AND mt.MarkaId IN (SELECT bf.Data FROM dbo.Split(@BrandFilter, ',') bf)
        ) Result
        WHERE RowNr > ((@PageNr-1) * 10) AND RowNr <= ((@PageNr) * 10)  
    END

此代码不同，

AND mt.MarkaId IN (SELECT bf.Data FROM dbo.Split(@BrandFilter, ',') bf)

谢谢..

Answer 1

你走了：

SELECT * FROM
(
    SELECT
        ROW_NUMBER() OVER(ORDER BY  
        CASE WHEN @SortType = '1' THEN mt.Ad END ASC,
        CASE WHEN @SortType = '2' THEN mt.Ad END DESC,
        CASE WHEN @SortType = '3' THEN mt.Fiyat END ASC,
        CASE WHEN @SortType = '4' THEN mt.Fiyat END DESC) AS RowNr, * 
    FROM @MainTable mt
    WHERE mt.Fiyat > @MinPrice AND mt.Fiyat < @MaxPrice
    AND (@BrandFilter = '' or mt.MarkaId IN (SELECT bf.Data FROM dbo.Split(@BrandFilter, ',') bf))
) Result
WHERE RowNr > ((@PageNr-1) * 10) AND RowNr <= ((@PageNr) * 10)

在分割之前，您必须添加检查@brandfilter是否为空

(@BrandFilter = '' or mt.MarkaId IN (SELECT bf.Data FROM dbo.Split(@BrandFilter, ',') bf))

Answer 2

像这样：

SELECT * FROM
(
    SELECT
            ROW_NUMBER() OVER(ORDER BY  
            CASE WHEN @SortType = '1' THEN mt.Ad END ASC,
            CASE WHEN @SortType = '2' THEN mt.Ad END DESC,
            CASE WHEN @SortType = '3' THEN mt.Fiyat END ASC,
            CASE WHEN @SortType = '4' THEN mt.Fiyat END DESC) AS RowNr, * 
    FROM @MainTable mt
    WHERE mt.Fiyat > @MinPrice AND mt.Fiyat < @MaxPrice     
     AND (mt.MarkaId IN (SELECT bf.Data FROM dbo.Split(@BrandFilter, ',') bf) OR @BrandFilter = '')
) Result
WHERE RowNr > ((@PageNr-1) * 10) AND RowNr <= ((@PageNr) * 10)

在if的上部分支中，AND子句的WHERE部分丢失;在下部分支中，检查MarkaId是@BrandFilter字符串的一部分。 <{1}}条件在未指定OR时使相同的条件为真。

如何在不使用if语句的情况下重写它？

2 个答案: