用于搜索具有无限数量的位字段的表的SQL设计方法
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考虑搜索包含公寓租赁信息的表:使用该界面的客户端选择在数据库中表示为位字段的多个条件,例如: > AllowPets 等等.. 我们面临的情况是,我们软件的每个新客户都有他们希望允许最终用户搜索的其他字段.位字段的数量可以达到数百个. 我有三种方法,我正在考虑并希望输入和/或不同的方法. >当前方法:添加更多位字段,动态构建SQL查询并使用EXEC执行:SET @SQL = @SQL’l.[NumUnits],’exec(@SQL)) 继续添加更多位字段. (300列的表?) >将数据表示为一个字段中的一系列位.我不清楚这种方法是否有效,考虑我上面提供的4个样本位字段.该字段可能如下所示:1011表示“hasparking”为false,但对所有其他字段为true.我不清楚你是如何构建一个你不关心它是否为真或假的查询,例如1?11,搜索者需要1,3和4才是真的但不关心’HasParking’是真还是假. 其他一些方法?这是一个众所周知的SQL设计模式吗? 谢谢你的帮助 KM-编辑评论 attribute table has a few other rows in it and is called listingattributes CREATE TABLE [dbo].[ListingAttributes]( [ListingID] [bigint] NOT NULL,[AttributeID] [int] IDENTITY(1,1) NOT NULL,[AttributeType] [smallint] NOT NULL,[BoardID] [int] NOT NULL,[ListingMLS] [varchar](30) NOT NULL,[PropertyTypeID] [char](3) NOT NULL,[StatusID] [varchar](2) NOT NULL,PRIMARY KEY CLUSTERED ( [AttributeID] ASC )WITH (PAD_INDEX = OFF,STATISTICS_NORECOMPUTE = OFF,IGNORE_DUP_KEY = OFF,ALLOW_ROW_LOCKS = ON,ALLOW_PAGE_LOCKS = ON,FILLFACTOR = 80) ON [PRIMARY] ) ON [PRIMARY] ;WITH GetMatchingAttributes AS ( SELECT ListingID,COUNT(AttributeID) AS CountOfMatches FROM ListingAttributes WHERE BoardID = 1 AND StatusID IN ('A') AND --PropertyTypeID in (select * from @PropertyType) --AND AttributeType IN (2,3,6) GROUP BY ListingID HAVING COUNT(AttributeID)=(3) ) SELECT count(l.listingid) FROM Listing l INNER JOIN GetMatchingAttributes m ON l.ListingID=m.ListingID -- where -- StatusID IN (select * from @Status) --AND --PropertyTypeID in (select * from @PropertyType) 1 1 0 NULL NULL 1 NULL 1 NULL NULL NULL 0.1934759 NULL NULL SELECT 0 NULL |--Compute Scalar(DEFINE:([Expr1006]=CONVERT_IMPLICIT(int,[Expr1012],0))) 1 2 1 Compute Scalar Compute Scalar DEFINE:([Expr1006]=CONVERT_IMPLICIT(int,0)) [Expr1006]=CONVERT_IMPLICIT(int,0) 1 0 0.001483165 11 0.1934759 [Expr1006] NULL PLAN_ROW 0 1 |--Stream Aggregate(DEFINE:([Expr1012]=Count(*))) 1 3 2 Stream Aggregate Aggregate NULL [Expr1012]=Count(*) 1 0 0.001483165 11 0.1934759 [Expr1012] NULL PLAN_ROW 0 1 |--Filter(WHERE:([Expr1005]=(3))) 1 4 3 Filter Filter WHERE:([Expr1005]=(3)) NULL 2471.109 0 0.00440886 9 0.1919928 NULL NULL PLAN_ROW 0 1 |--Compute Scalar(DEFINE:([Expr1005]=CONVERT_IMPLICIT(int,[Expr1011],0))) 1 5 4 Compute Scalar Compute Scalar DEFINE:([Expr1005]=CONVERT_IMPLICIT(int,0)) [Expr1005]=CONVERT_IMPLICIT(int,0) 9185.126 0 0.01422281 11 0.1875839 [Expr1005] NULL PLAN_ROW 0 1 |--Stream Aggregate(GROUP BY:(.[dbo].[ListingAttributes].[ListingID]) DEFINE:([Expr1011]=Count(*))) 1 6 5 Stream Aggregate Aggregate GROUP BY:(.[dbo].[ListingAttributes].[ListingID]) [Expr1011]=Count(*) 9185.126 0 0.01422281 11 0.1875839 [Expr1011] NULL PLAN_ROW 0 1 |--Index Seek(OBJECT:(.[dbo].[ListingAttributes].[_dta_index_ListingAttributes_BoardID_ListingID__AttributeType_PropertyTypeID_StatusID_6_7]),SEEK:(.[dbo].[ListingAttributes].[BoardID]=(1)),WHERE:(.[dbo].[ListingAttributes].[StatusID]='A' AND (.[dbo].[ListingAttributes].[AttributeType]=(2) OR .[dbo].[ListingAttributes].[AttributeType]=(3) OR .[dbo].[ListingAttributes].[AttributeType]=(6))) ORDERED FORWARD) 1 7 6 Index Seek Index Seek OBJECT:(.[dbo].[ListingAttributes].[_dta_index_ListingAttributes_BoardID_ListingID__AttributeType_PropertyTypeID_StatusID_6_7]),WHERE:(.[dbo].[ListingAttributes].[StatusID]='A' AND (.[dbo].[ListingAttributes].[AttributeType]=(2) OR .[dbo].[ListingAttributes].[AttributeType]=(3) OR .[dbo].[ListingAttributes].[AttributeType]=(6))) ORDERED FORWARD .[dbo].[ListingAttributes].[ListingID],.[dbo].[ListingAttributes].[AttributeID],.[dbo].[ListingAttributes].[AttributeType],.[dbo].[ListingAttributes].[StatusID] 16050.41 0.09677318 0.0315279 26 0.1283011 .[dbo].[ListingAttributes].[ListingID],.[dbo].[ListingAttributes].[StatusID] NULL PLAN_ROW 0 1 (7 row(s) affected) 解决方法这样的事情可能适合你:(编辑:源码网) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |