带 TVP 参数的条件 WHERE 子句

Question

我正在构建一个食谱网站，我正在尝试创建一个带有 table 值参数的存储过程，但是运行遇到了一些问题。

所以 TVP 是根据用户 select 在尝试搜索食谱时的复选框列表来填充的。然后我想展示基于这些 select 离子的配方，因此我在我的存储过程中使用了 TVP。

但是，当用户没有select 复选框列表之一中的任何选项时，我希望查询显示所有记录（对于每个部分）。当我尝试执行此操作时，查询立即 return 没有结果。

TVP 设置和逻辑

类别	难度[=65=]	持续时间
肉类	简单	0-15 分钟
string.Empty	平均	30-45 分钟
鱼	困难	string.Empty

我希望程序根据类别、难度和持续时间中的所有选项 select 过滤每个食谱。 IE。在这种情况下，我希望存储过程 return 所有具有 Category = "Meat" 或 "Fish" 的食谱；难度 =“简单”或“平均”或“困难”，持续时间 =“0-15 分钟”或“30-45 分钟”。

例如，如果类别中不存在任何值，则存储过程应该return 来自所有类别的食谱，并且仅根据具有值的列进行过滤。

到目前为止的工作代码

ALTER PROCEDURE uspPesquisarReceita (@TVP dbo.Filters READONLY)
AS
BEGIN
    SELECT R.RecipeName, C.Category, DF.Dificulty, D.Duration, R.Rating, R.Publication, R.Photo, R.Views, R.IDRecipe
        FROM dbo.Recipes R 
        LEFT JOIN dbo.Categories C ON R.IDCategory = C.IDCategory 
        LEFT JOIN dbo.Dificulty DF ON R.IDDificulty = DF.IDDificulty
        LEFT JOIN dbo.Duration D ON R.IDDuration = D.IDDuration
        WHERE R.IDStatus = 1 
        AND (C.Category IN (SELECT Category FROM @TVP)
        AND DF.Dificulty IN (SELECT Dificulty FROM @TVP) 
        AND D.Duration IN (SELECT Duration FROM @TVP))
END

仅当我在所有三个复选框列表（称为类别、难度和持续时间）中 select 选项时，此代码才有效。

我试过的代码#1

ALTER PROCEDURE uspPesquisarReceita (@TVP dbo.Filters READONLY)
    AS
    BEGIN
        SELECT R.RecipeName, C.Category, DF.Dificulty, D.Duration, R.Rating, R.Publication, R.Photo, R.Views, R.IDRecipe
            FROM dbo.Recipes R 
            LEFT JOIN dbo.Categories C ON R.IDCategory = C.IDCategory 
            LEFT JOIN dbo.Dificulty DF ON R.IDDificulty = DF.IDDificulty
            LEFT JOIN dbo.Duration D ON R.IDDuration = D.IDDuration
            WHERE R.IDStatus = 1 
            AND (C.Category IN (CASE WHEN NOT EXISTS (SELECT Category FROM @TVP)
                                 THEN
                                  (SELECT R.RecipeName, C.Category, DF.Dificulty, D.Duration, 
                                  R.Rating, R.Publication, R.Photo, R.Views, R.IDRecipe
                                  FROM dbo.Recipes R 
                                  LEFT JOIN dbo.Categories C ON R.IDCategory = C.IDCategory 
                                  LEFT JOIN dbo.Dificulty DF ON R.IDDificulty = DF.IDDificulty
                                  LEFT JOIN dbo.Duration D ON R.IDDuration = D.IDDuration
                                  WHERE R.IDStatus = 1)
                                 ELSE (SELECT Category FROM @TVP) 
            AND DF.Dificulty IN (SELECT Dificulty FROM @TVP)
                                  *same as above*
            AND D.Duration IN (SELECT Duration FROM @TVP))
                                  *same as above*
    END

我试过的代码#2（只有类别的例子）

ALTER PROCEDURE uspPesquisarReceita (@TVP dbo.Filters READONLY)
        AS
        BEGIN
            IF NOT EXISTS (SELECT Category FROM @TVP)
                SELECT R.RecipeName, C.Category, DF.Dificulty, D.Duration, R.Rating, 
                R.Publication, R.Photo, R.Views, R.IDRecipe
                FROM dbo.Recipes R 
                LEFT JOIN dbo.Categories C ON R.IDCategory = C.IDCategory 
                LEFT JOIN dbo.Dificulty DF ON R.IDDificulty = DF.IDDificulty
                LEFT JOIN dbo.Duration D ON R.IDDuration = D.IDDuration
                WHERE R.IDStatus = 1
                AND DF.Dificulty IN (SELECT Dificulty FROM @TVP) 
                AND D.Duration IN (SELECT Duration FROM @TVP))
            ELSE
                SELECT R.RecipeName, C.Category, DF.Dificulty, D.Duration, R.Rating, 
                R.Publication, R.Photo, R.Views, R.IDRecipe
                FROM dbo.Recipes R 
                LEFT JOIN dbo.Categories C ON R.IDCategory = C.IDCategory 
                LEFT JOIN dbo.Dificulty DF ON R.IDDificulty = DF.IDDificulty
                LEFT JOIN dbo.Duration D ON R.IDDuration = D.IDDuration
                WHERE R.IDStatus = 1 
                AND (C.Category IN (SELECT Category FROM @TVP)
                AND DF.Dificulty IN (SELECT Dificulty FROM @TVP) 
                AND D.Duration IN (SELECT Duration FROM @TVP))
    END

None 这两次尝试都没有结果。你能帮我吗？我错过了什么？

谢谢！

Answer 1

我将提出类似以下的建议 - 尽管正如 Dale 指出的那样，当您的 @TVP 值填充了不同的过滤器组合时，它会很方便地准确查看它的外观。但是，在此期间，请尝试一下，看看会得到什么结果。

ALTER PROCEDURE uspPesquisarReceita (@TVP dbo.Filters READONLY)
AS
BEGIN
    SELECT R.RecipeName, C.Category, DF.Dificulty, D.Duration, R.Rating, R.Publication, R.Photo, R.Views, R.IDRecipe
        FROM dbo.Recipes R 
        LEFT JOIN dbo.Categories C ON R.IDCategory = C.IDCategory 
        LEFT JOIN dbo.Dificulty DF ON R.IDDificulty = DF.IDDificulty
        LEFT JOIN dbo.Duration D ON R.IDDuration = D.IDDuration
        WHERE R.IDStatus = 1 
        AND
        (
            (C.Category IN (SELECT Category FROM @TVP))
            OR
            (NOT EXISTS (SELECT 1 FROM @TVP WHERE LTRIM(ISNULL(Category, '')) <> ''))
        )
        AND 
        (
            (DF.Dificulty IN (SELECT Dificulty FROM @TVP))
            OR
            (NOT EXISTS (SELECT 1 FROM @TVP WHERE LTRIM(ISNULL(Dificulty, '')) <> ''))
        )
        AND 
        (
            (D.Duration IN (SELECT Duration FROM @TVP))
            OR
            (NOT EXISTS (SELECT 1 FROM @TVP WHERE LTRIM(ISNULL(Duration, '')) <> ''))
        )
END

基本上，我假设如果用户没有为特定过滤器（类别、难度或持续时间）勾选任何选项，那么@TVP table 中将没有行相应列中的值。（如果这个假设不正确，那么我们将回到 Dale 的建议，即查看有关如何填充 @TVP 变量的更多详细信息 - 即您的应用程序端代码）

带 TVP 参数的条件 WHERE 子句

Conditional WHERE clauses with TVP parameter

sql

tsql

sql-server

stored-procedures