T-SQL插入 - 选择表变量是很慢(T-SQL Insert - Select in Table

2019-06-25 04:55发布

我有一个表变量,我在它插入使用一些值“INSERT INTO - 选择”的声明。 选择是很少的组合联接,并且当它被单独执行它需要3秒。 问题是,整个代码需要3-4分钟即可执行。 我不知道是否有这个特殊的原因。

这是我的表变量声明:

DECLARE @Result TABLE 
(
     ProductID NVARCHAR(25) PRIMARY KEY
    ,ProductName NVARCHAR(100)
    ,ProductCategoryID TINYINT
    ,ProductCategory  NVARCHAR(50)
    ,ProductSubCategoryID TINYINT
    ,ProductSubCategory  NVARCHAR(50)
    ,BrandID TINYINT
    ,Brand  NVARCHAR(50)
)

我有一个其它表变量我与一些数据初始化,这是它的结构:

DECLARE @TempTable TABLE
(
    ProtoSurveyID INT,
    ProductID NVARCHAR(25) PRIMARY KEY
)

和下面的代码是我的问题发言(插入 - 选择):

INSERT INTO @Result (ProductID,ProductName,ProductCategoryID,ProductCategory,ProductSubCategoryID,ProductSubCategory,BrandID,Brand)
SELECT 
         Products.ProductID  AS ProductID
        ,Products.ProductName  AS ProductName
        ,ProductCategories.ProductCategoryID  AS ProductCategoryID
        ,ProductCategories.ProductCategory   AS ProductCategory
        ,ProductSubCategories.ProductSubCategoryID  AS ProductSubCategoryID
        ,ProductSubCategories.ProductSubCategory  AS ProductSubCategory
        ,Brands.BrandID AS BrandID
        ,Brands.Brand  AS Brand
FROM 
(
        SELECT     
               CAST(A.Col001 AS tinyint) AS ProductCategoryID
              ,CAST(A.Col002 AS tinyint) AS BrandID
              ,CAST(A.Col003 AS nvarchar(25)) AS ProductID
              ,CAST(A.Col004 AS nvarchar(100)) AS ProductName
              ,CAST(A.Col006 As tinyint) AS ProductSubCategoryID
              ,B.ProtoSurveyID
        FROM DataSetsMaterializedDataSqlvariant A 
        INNER JOIN @TempTable B 
        ON B.ProductID=CAST(A.Col003 AS nvarchar(25))
        WHERE DataSetsMaterializedInternalRowsetID = 3 
) Products      
INNER JOIN
(
         SELECT CAST(A.Col001 AS tinyint) AS BrandID
              , CAST(A.Col002 AS nvarchar(50)) AS Brand
         FROM DataSetsMaterializedDataSqlvariant A
         WHERE DataSetsMaterializedInternalRowsetID = 1
)Brands On Products.BrandID=Brands.BrandID
INNER JOIN
(
         SELECT CAST(A.Col001 AS tinyint) AS ProductCategoryID
                ,CAST(A.Col002 AS nvarchar(50)) AS ProductCategory
         FROM DataSetsMaterializedDataSqlvariant A
         WHERE DataSetsMaterializedInternalRowsetID = 2
) ProductCategories On Products.ProductCategoryID=ProductCategories.ProductCategoryID
INNER JOIN
(
         SELECT CAST(A.Col001 AS tinyint) AS ProductSubCategoryID
              , CAST(A.Col002 AS nvarchar(50)) AS ProductSubCategory
         FROM DataSetsMaterializedDataSqlvariant A
         WHERE DataSetsMaterializedInternalRowsetID = 11
) ProductSubCategories on Products.ProductSubCategoryID=ProductSubCategories.ProductSubCategoryID

正如我之前说的,如果我评论的插入线的查询需要3秒,否则 - 很长一段时间。

编辑:这是我的执行计划 - 大部分成本是表扫描,但为什么需要时插入是让这么多的时间,恰好快速无过?

后续是我的新的内联函数:

CREATE FUNCTION [dbo].[fn_XxCustom_RetailAudits_GetProductsForFilter]
(
    @SecurityObjectUserID BIGINT
)
RETURNS TABLE
AS
RETURN

    WITH CTE(ProtoSurveyID,ProductID) AS
    (
        SELECT  DISTINCT  CAST(B.ProtoSurveyID AS INT)
                         ,CAST(A.Col002 AS NVARCHAR(25)) AS ProductID
        FROM DataSetsMaterializedDataSqlvariant A
        JOIN SurveyInstances B ON A.Col001=B.SurveyInstanceID AND CAST(B.ProtoSurveyID AS INT) IN (SELECT ProtoSurveyID FROM dbo.fn_Filter_GetProtoSurveysAllowedShort(@SecurityObjectUserID, 'CLIENTACCESS',NULL))
        WHERE DataSetsMaterializedInternalRowsetID = 5
    )
    SELECT 
             Products.ProductID  AS ProductID
            ,Products.ProductName  AS ProductName
            ,ProductCategories.ProductCategoryID  AS ProductCategoryID
            ,ProductCategories.ProductCategory   AS ProductCategory
            ,ProductSubCategories.ProductSubCategoryID  AS ProductSubCategoryID
            ,ProductSubCategories.ProductSubCategory  AS ProductSubCategory
            ,Brands.BrandID AS BrandID
            ,Brands.Brand  AS Brand
    FROM 
    (
            SELECT     
                   CAST(A.Col001 AS tinyint) AS ProductCategoryID
                  ,CAST(A.Col002 AS tinyint) AS BrandID
                  ,CAST(A.Col003 AS nvarchar(25)) AS ProductID
                  ,CAST(A.Col004 AS nvarchar(100)) AS ProductName
                  ,CAST(A.Col006 As tinyint) AS ProductSubCategoryID
                  ,B.ProtoSurveyID
            FROM CTE B
            INNER JOIN DataSetsMaterializedDataSqlvariant A 
            ON B.ProductID=CAST(A.Col003 AS nvarchar(25))
            WHERE DataSetsMaterializedInternalRowsetID = 3 
    ) Products      
    INNER JOIN
    (
             SELECT CAST(A.Col001 AS tinyint) AS BrandID
                   ,CAST(A.Col002 AS nvarchar(50)) AS Brand
             FROM DataSetsMaterializedDataSqlvariant A
             WHERE DataSetsMaterializedInternalRowsetID = 1
    )Brands On Products.BrandID=Brands.BrandID
    INNER JOIN
    (
             SELECT  CAST(A.Col001 AS tinyint) AS ProductCategoryID
                    ,CAST(A.Col002 AS nvarchar(50)) AS ProductCategory
             FROM DataSetsMaterializedDataSqlvariant A
             WHERE DataSetsMaterializedInternalRowsetID = 2
    ) ProductCategories On Products.ProductCategoryID=ProductCategories.ProductCategoryID
    INNER JOIN
    (
             SELECT  CAST(A.Col001 AS tinyint) AS ProductSubCategoryID
                    ,CAST(A.Col002 AS nvarchar(50)) AS ProductSubCategory
             FROM DataSetsMaterializedDataSqlvariant A
             WHERE DataSetsMaterializedInternalRowsetID = 11
    ) ProductSubCategories on Products.ProductSubCategoryID=ProductSubCategories.ProductSubCategoryID

GO

我再次运行速度慢。 任何想法如何优化呢?

Answer 1:

即插入到表变量的查询不能有一个平行的计划。

尝试使用#temp表而不是允许SELECT被并行化。



文章来源: T-SQL Insert - Select in Table variable is very slow