Question

我有一份宠物清单：

我需要为所有者表中的每只宠物找到一个正确的拥有者

为了将每只宠物与主人正确匹配，我需要使用一个特殊的匹配表，如下所示：

因此，对于PetID = 2的宠物，我需要找到一个基于三个字段匹配的所有者：

    Pet.Zip = Owner.Zip 
    and Pet.OwnerName = Owner.Name 
    and Pet.Document = Owner.Document

在我们的示例中，它将如下工作：

 select top 1 OwnerID from owners
         where Zip = 23456 
         and Name = 'Alex' 
         and Document = 'a.csv'

如果找不到OwnerID，那么我需要根据2个字段进行匹配（不使用优先级最高的字段）

在我们的例子中：

 select top 1 OwnerID from owners where
             Name = 'Alex' 
             and Document = 'a.csv'

由于没有找到记录，我们需要匹配较少的字段。在我们的例子中：

select top 1 OwnerID from owners where Document = 'a.csv'

现在，我们找到了OwnerID = 6的所有者。

现在我们需要更新ownerID = 6的宠物，然后我们可以处理下一只宠物。

我现在唯一能做到这一点的方法是使用循环或游标+动态SQL。

是否有可能在没有循环+动态sql的情况下实现这一点？也许STUFF + Pivot不知何故？

sql fiddle：http://sqlfiddle.com/#!18/10982/1/0

示例数据：

create table  temp_builder
(
    PetID int not null,
    Field varchar(30) not null,
    MatchTo varchar(30) not null,
    Priority int not null
)

insert into temp_builder values
(1,'Address', 'Addr',4),
(1,'Zip', 'Zip', 3),
(1,'Country', 'Country', 2),
(1,'OwnerName', 'Name',1),
(2,'Zip', 'Zip',3),
(2,'OwnerName','Name', 2),
(2,'Document', 'Document', 1),
(3,'Country', 'Country', 1)


create table temp_pets
(
    PetID int null,
    Address varchar(100) null,
    Zip int null,
    Country varchar(100) null,
    Document varchar(100) null,
    OwnerName varchar(100) null,
    OwnerID int null,
    Field1 bit null,
    Field2 bit null
)

insert into temp_pets values
(1, '123 5th st', 12345, 'US', 'test.csv', 'John', NULL, NULL, NULL),
(2, '234 6th st', 23456, 'US', 'a.csv', 'Alex', NULL, NULL, NULL),
(3, '345 7th st', 34567, 'US', 'b.csv', 'Mike', NULL, NULL, NULL)

create table temp_owners
(
    OwnerID int null,
    Addr varchar(100) null,
    Zip int null,
    Country varchar(100) null,
    Document varchar(100) null,
    Name varchar(100) null,
    OtherField bit null,
    OtherField2 bit null,
)

insert into temp_owners values
(1, '456 8th st',  45678, 'US', 'c.csv', 'Mike',  NULL, NULL),
(2, '678 9th st',  45678, 'US', 'b.csv', 'John',  NULL, NULL),
(3, '890 10th st', 45678, 'US', 'b.csv', 'Alex',  NULL, NULL),
(4, '901 11th st', 23456, 'US', 'b.csv', 'Alex',  NULL, NULL),
(5, '234 5th st',  12345, 'US', 'b.csv', 'John',  NULL, NULL),
(6, '123 5th st',  45678, 'US', 'a.csv', 'John',  NULL, NULL)

编辑：我被一些很棒的建议和回应所淹没。我对它们进行了测试，很多人都对我很好。不幸的是，我只能奖励一个解决方案。

Answer 1

通过将用于比较的字段视为每个宠物的位集中的条目，可以避免使用游标，循环和动态SQL。根据位条目（FieldRank rank列）计算每个优先级的位集（FieldSetRank列）。

宠物和所有者表必须是不可分割的，以便可以比较字段及其相关值。已匹配的每个字段和值都分配给相应的FieldRank。然后基于匹配值（MatchSetRank）计算新的比特集。仅返回匹配集（MatchSetRank）等于所需集（FieldSetRank）的记录。

查询执行一个最终排名以返回具有最高MatchSetRank的记录（在保持优先级标准的同时匹配最高列数的记录。以下T-SQL演示了这个概念。

;WITH CTE_Builder
 AS
 (
     SELECT  [PetID]
            ,[Field]
            ,[Priority]
            ,[MatchTo]
            ,POWER(2, [Priority] - 1) AS [FieldRank] -- Define the field ranking as bit set numbered item.
            ,SUM(POWER(2, [Priority] - 1)) OVER (PARTITION BY [PetID] ORDER BY [Priority] ROWS UNBOUNDED PRECEDING) FieldSetRank -- Sum all the bit set IDs to define what constitutes a completed field set ordered by priority.
     FROM   temp_builder
 ),
CTE_PetsUnpivoted
AS
(   -- Unpivot pets table and assign Field Rank and Field Set Rank.
    SELECT   [PetsUnPivot].[PetID]
            ,[PetsUnPivot].[Field]
            ,[Builder].[MatchTo]
            ,[PetsUnPivot].[FieldValue]
            ,[Builder].[Priority]
            ,[Builder].[FieldRank]
            ,[Builder].[FieldSetRank]

    FROM 
       (
            SELECT [PetID], [Address], CAST([Zip] AS VARCHAR(100)) AS [Zip], [Country], [Document], [OwnerName]
            FROM temp_pets
        ) [Pets]
    UNPIVOT
       (FieldValue FOR Field IN 
          ([Address], [Zip], [Country], [Document], [OwnerName])
    ) AS [PetsUnPivot]
    INNER JOIN [CTE_Builder] [Builder] ON [PetsUnPivot].PetID = [Builder].PetID AND [PetsUnPivot].Field = [Builder].Field
),
CTE_Owners
AS
(
    -- Unpivot Owners table and join with unpivoted Pets table on field name and field value.  
    -- Next assign Pets field rank then calculated the field set rank (MatchSetRank) based on actual matches made.
    SELECT   [OwnersUnPivot].[OwnerID]
            ,[Pets].[PetID]
            ,[OwnersUnPivot].[Field]
            ,[Pets].Field AS [PetField]
            ,[Pets].FieldValue as PetFieldValue
            ,[OwnersUnPivot].[FieldValue]
            ,[Pets].[Priority]
            ,[Pets].[FieldRank]
            ,[Pets].[FieldSetRank]
            ,SUM([FieldRank]) OVER (PARTITION BY [Pets].[PetID], [OwnersUnPivot].[OwnerID] ORDER BY [Pets].[Priority] ROWS UNBOUNDED PRECEDING) MatchSetRank
    FROM 
       (
            SELECT [OwnerID], [Addr], CAST([Zip] AS VARCHAR(100)) AS [Zip], [Country], [Document], [Name]
            FROM temp_owners
        ) [Owners]
    UNPIVOT
       (FieldValue FOR Field IN 
          ([Addr], [Zip], [Country], [Document], [Name])
    ) AS [OwnersUnPivot]
    INNER JOIN [CTE_PetsUnpivoted] [Pets] ON [OwnersUnPivot].[Field] = [Pets].[MatchTo] AND [OwnersUnPivot].[FieldValue] = [Pets].[FieldValue]
),
CTE_FinalRanking
AS
(
    SELECT   [PetID]
            ,[OwnerID]
            -- -- Calculate final rank, if multiple matches have the same rank then multiple rows will be returned per pet. 
            -- Change the “RANK()” function to "ROW_NUMBER()" to only return on result per pet.
            ,RANK() OVER (PARTITION BY [PetID] ORDER BY [MatchSetRank] DESC) AS [FinalRank] 
    FROM    CTE_Owners
    WHERE   [FieldSetRank] = [MatchSetRank] -- Only return records where the field sets calculated based on 
                                            -- actual matches is equal to desired field set ranks. This will 
                                            -- eliminate matches where the number of fields that meets the 
                                            -- criteria is the same but does not meet priority requirements. 
)
SELECT   [PetID]
        ,[OwnerID]
FROM    CTE_FinalRanking
WHERE   [FinalRank] = 1

Answer 2

完成这项工作是一件非常艰巨的任务......以下是我的工作方式：

首先，您需要添加一个表，该表将包含半where子句，即基于temp_builder表的即用型条件。此外，由于你有5列，我认为最多可以有5个条件。这是表的创建：

CREATE TABLE [dbo].[temp_builder_with_where](
    [petid] [int] NULL,
    [priority1] [bit] NULL,
    [priority2] [bit] NULL,
    [priority3] [bit] NULL,
    [priority4] [bit] NULL,
    [priority5] [bit] NULL,
    [whereClause] [varchar](200) NULL
) 
--it's good to create index, for better performance
create clustered index idx on [temp_builder_with_where]([petid])

insert into temp_builder_with_where
select petid,[priority1],[priority2],[priority3],[priority4],[priority5],
         '[pets].' + CAST(field as varchar(100)) + ' = [owners].' + CAST(matchto as varchar(100)) [whereClause]
from (
select petid, field, matchto, [priority],
        1 Priority1,
        case when [priority] > 1 then 1 else 0 end Priority2,
        case when [priority] > 2 then 1 else 0 end Priority3,
        case when [priority] > 3 then 1 else 0 end Priority4,
        case when [priority] > 4 then 1 else 0 end Priority5       
from temp_builder) [builder]

现在我们将循环遍历该表。你告诉我这个表包含8000行，所以我选择了其他方式：动态查询现在只会为一个petid插入结果。

为了做到这一点，我们需要表来存储我们的结果：

CREATE TABLE [dbo].[TableWithNewId](
    [petid] [int] NULL,
    [ownerid] [int] NULL,
    [priority] [int] NULL
)

现在，动态SQL用于insert语句：

declare @query varchar(1000) = ''
declare @i int, @max int
set @i = 1
select @max = MAX(petid) from temp_builder_with_where

while @i <= @max
begin

    set @query = ''

    select @query = @query + whereClause1 + whereClause2 + whereClause3 + whereClause4 + whereClause5 + ' union all ' from (
    select 'insert into [MY_DATABASE].dbo.TableWithNewId  select ' + CAST(petid as varchar(3)) + ' [petid], [owners].ownerid, 1 [priority] from temp_pets [pets], temp_owners [owners] where (' + [where_petid] + [where1] + ')' [whereClause1],
           case when [where2] is null then '' else ' union all select ' + CAST(petid as varchar(3)) + ' [petid], [owners].ownerid, 2 [priority] from temp_pets [pets], temp_owners [owners] where (' + [where_petid] + [where2] + ')' end [whereClause2], 
           case when [where3] is null then '' else ' union all select ' + CAST(petid as varchar(3)) + ' [petid], [owners].ownerid, 3 [priority] from temp_pets [pets], temp_owners [owners] where (' + [where_petid] + [where3] + ')' end [whereClause3], 
           case when [where4] is null then '' else ' union all select ' + CAST(petid as varchar(3)) + ' [petid], [owners].ownerid, 4 [priority] from temp_pets [pets], temp_owners [owners] where (' + [where_petid] + [where4] + ')' end [whereClause4], 
           case when [where5] is null then '' else ' union all select ' + CAST(petid as varchar(3)) + ' [petid], [owners].ownerid, 5 [priority] from temp_pets [pets], temp_owners [owners] where (' + [where_petid] + [where5] + ')' end [whereClause5]
    from (
            select petid, 'petid = ' + CAST(petid as nvarchar(3)) [where_petid],
               (select ' and ' + whereClause from temp_builder_with_where where petid = t.petid and priority1 = 1 for xml path(''),type).value('(.)[1]', 'varchar(500)') [where1],
               (select ' and ' + whereClause from temp_builder_with_where where petid = t.petid and priority2 = 1 for xml path(''),type).value('(.)[1]', 'varchar(500)') [where2],
               (select ' and ' + whereClause from temp_builder_with_where where petid = t.petid and priority3 = 1 for xml path(''),type).value('(.)[1]', 'varchar(500)') [where3],
               (select ' and ' + whereClause from temp_builder_with_where where petid = t.petid and priority4 = 1 for xml path(''),type).value('(.)[1]', 'varchar(500)') [where4],
               (select ' and ' + whereClause from temp_builder_with_where where petid = t.petid and priority5 = 1 for xml path(''),type).value('(.)[1]', 'varchar(500)') [where5]
       from temp_builder_with_where [t]
       where petid = @i
        group by petid
    ) a
    ) a
    --remove last union all
    set @query = left(@query, len(@query) - 10)
    exec (@query)

    set @i = @i + 1

end

请注意，您必须使用您的数据库名称替换上述代码中的[MY_DATABASE] 。从您的示例数据中，这将是查询select * from TableWithNewId：

的结果

PetId|OwnerId|Priority
1    |6      |4
2    |4      |2
2    |4      |3
3    |1      |1
3    |2      |1
3    |3      |1
3    |4      |1
3    |5      |1
3    |6      |1

根据该结果，您现在可以根据最低优先级将OwnerId分配给PetId（好吧，您没有说明如何处理发现多个OwnerId的情况为了相同的优先权。）

Answer 3

我马上就说要节省你的时间：

我的解决方案使用动态SQL。 MichałTurczyn正确地指出，当比较列的名称存储在数据库中时，你无法避免它。
我的解决方案使用循环。而且我坚信你不会用纯SQL查询解决这个问题，它会对你声明的数据大小（表有> 1M记录）运行得足够快。您描述的逻辑本质上意味着迭代 - 从更大的匹配字段集到更低的集合。 SQL作为查询语言并不是为了涵盖这些棘手的场景而设计的。您可以尝试使用纯SQL查询来解决您的问题，但即使您设法构建此类查询，它也将非常棘手，复杂且不清楚。我不是这种解决方案的粉丝。这就是为什么我甚至没有深入到这个方向。
另一方面，我的解决方案不需要创建临时表，这是一个优势。

鉴于此，我的方法很简单：

有一个外部循环从最大的匹配器集（所有匹配的字段）迭代到最小的匹配器集（一个字段）。在第一次迭代中，当我们还不知道宠物数据库中存储了多少匹配器时，我们会阅读并使用它们。在下一次迭代中，我们将使用的匹配器的数量减少1（删除具有最高优先级的匹配器）。
内部循环遍历当前的匹配器集并构建WHERE子句，用于比较Pets和Owners表之间的字段。
执行当前查询，如果某个所有者符合给定条件，我们会从外部循环中断。

以下是实现此逻辑的代码：

DECLARE @PetId INT = 2;

DECLARE @MatchersLimit INT;
DECLARE @OwnerID INT;

WHILE (@MatchersLimit IS NULL OR @MatchersLimit > 0) AND @OwnerID IS NULL
BEGIN

    DECLARE @CurrMatchFilter VARCHAR(max) = ''
    DECLARE @Field VARCHAR(30)
    DECLARE @MatchTo VARCHAR(30)
    DECLARE @CurrMatchersNumber INT = 0;

    DECLARE @GetMatchers CURSOR;
    IF @MatchersLimit IS NULL
        SET @GetMatchers = CURSOR FOR SELECT Field, MatchTo FROM temp_builder WHERE PetID = @PetId ORDER BY Priority ASC;
    ELSE
        SET @GetMatchers = CURSOR FOR SELECT TOP (@MatchersLimit) Field, MatchTo FROM temp_builder WHERE PetID = @PetId ORDER BY Priority ASC;

    OPEN @GetMatchers;
    FETCH NEXT FROM @GetMatchers INTO @Field, @MatchTo;
    WHILE @@FETCH_STATUS = 0
    BEGIN
        IF @CurrMatchFilter <> '' SET @CurrMatchFilter = @CurrMatchFilter + ' AND ';
        SET @CurrMatchFilter = @CurrMatchFilter + ('temp_pets.' + @Field + ' = ' + 'temp_owners.' + @MatchTo);
        FETCH NEXT FROM @GetMatchers INTO @field, @matchTo;
        SET @CurrMatchersNumber = @CurrMatchersNumber + 1;
    END
    CLOSE @GetMatchers;
    DEALLOCATE @GetMatchers;

    IF @CurrMatchersNumber = 0 BREAK;

    DECLARE @CurrQuery nvarchar(max) = N'SELECT @id = temp_owners.OwnerID FROM temp_owners INNER JOIN temp_pets ON (' + CAST(@CurrMatchFilter AS NVARCHAR(MAX)) + N') WHERE temp_pets.PetID = ' + CAST(@PetId AS NVARCHAR(MAX));
    EXECUTE sp_executesql @CurrQuery, N'@id int OUTPUT', @id=@OwnerID OUTPUT;

    IF @MatchersLimit IS NULL
        SET @MatchersLimit = @CurrMatchersNumber - 1;
    ELSE
        SET @MatchersLimit = @MatchersLimit - 1;

END

SELECT @OwnerID AS OwnerID, @MatchersLimit + 1 AS Matched;

效果考虑因素

这种方法基本上有2个查询：

SELECT Field, MatchTo FROM temp_builder WHERE PetID = @PetId;

您应该在PetID表中的temp_builder字段上添加索引，此查询将执行得非常快。
SELECT @id = temp_owners.OwnerID FROM temp_owners INNER JOIN temp_pets ON (temp_pets.Document = temp_owners.Document AND temp_pets.OwnerName = temp_owners.Name AND temp_pets.Zip = temp_owners.Zip AND ...) WHERE temp_pets.PetID = @PetId;

这个查询看起来很可怕，因为它加入了两个大表 - temp_owners和temp_pets。但是temp_pets表被PetID列过滤，只能生成一条记录。因此，如果您在temp_pets.PetID列上有索引（并且您应该将此列看作主键），则查询将导致temp_owners表的扫描。即使对于超过1M行的表，这种扫描也不会花费很长时间。如果查询仍然太慢，您可以考虑为匹配器中使用的temp_owners表的列添加索引（Addr，Zip等）。添加索引有缺点，例如更大的数据库和更慢的插入/更新操作。因此，在temp_owners列上添加索引之前，请检查没有索引的表上的查询速度。

Answer 4

我不确定我是否正确得到了最终结果，但我建议使用几个公用表表达式来使用动态SQL生成一批更新语句（我担心它不能在没有动态SQL的情况下完成，然后使用Exec(sql)执行它们。

这种方法的好处是它不涉及循环或游标。

我生成的每个更新语句都在宠物和所有者表之间使用inner join，使用所有者表所有者ID更新pets表的所有者ID，使用构建器表中的映射作为{的基础{1}}条款第一个cte负责从构建器表生成on子句，第二个负责生成更新语句。
最后，我将第二个CTE中的所有SQL语句选择为单个on变量并执行它。

我解决优先级问题的方法是为每组优先级生成一个更新语句，从包含所有优先级开始，并从下一个SQL语句中排除值，首先排除最高优先级，直到我为止留下nvarchar(max)子句只映射一组列。

所以，首先要声明一个变量来保存生成的更新语句：

on

现在，第一个CTE正在使用DECLARE @Sql nvarchar(max) = '' cross apply和stuff来为每对for xml和on生成petId子句}：

Priority

第二个CTE为每个;WITH OnClauseCTE AS ( SELECT DISTINCT PetId, Priority, OnClause FROM temp_builder t0 CROSS APPLY ( SELECT STUFF ( ( SELECT ' AND p.'+ Field +' = o.'+ MatchTo FROM temp_builder t1 WHERE PetID = t0.PetId AND Priority <= t0.Priority FOR XML PATH('') ) , 1, 5, '') As OnClause ) onClauseGenerator )和UPDATE组合生成一个petId语句：

Priority

最后，从UpdateStatementCTE生成一批更新语句：

, UpdateStatementCTE AS
(
    SELECT  PetId,
            Priority,
            'UPDATE p 
            SET OwnerID = o.OwnerID 
            FROM temp_pets p 
            INNER JOIN temp_owners o ON ' + OnClause + ' 
            WHERE p.PetId = '+ CAST(PetId as varchar(10)) +'
            AND p.OwnerID IS NULL; -- THIS IS CRITICAL!
            ' AS SQL
    FROM OnClauseCTE
)

当您打印SELECT @Sql = @Sql + SQL FROM UpdateStatementCTE ORDER BY PetId, Priority DESC -- ORDER BY Priority is CRITICAL!的内容时，order by PetId严格有助于提高可读性。但是，@Sql子句的Priority DESC部分是严重，因为我们要先执行最高优先级，最后执行最低优先级。

现在，order by包含此（缩写）：

@Sql

正如您所看到的，每个更新语句都在构建器表中表示，并且只有在前一个更新语句尚未更新时才会更改所有者ID，因为UPDATE p SET OwnerID = o.OwnerID FROM temp_pets p INNER JOIN temp_owners o ON p.Address = o.Addr AND p.Zip = o.Zip AND p.Country = o.Country AND p.OwnerName = o.Name WHERE p.PetId = 1 AND p.OwnerID IS NULL; ... UPDATE p SET OwnerID = o.OwnerID FROM temp_pets p INNER JOIN temp_owners o ON p.OwnerName = o.Name WHERE p.PetId = 1 AND p.OwnerID IS NULL; ... UPDATE p SET OwnerID = o.OwnerID FROM temp_pets p INNER JOIN temp_owners o ON p.OwnerName = o.Name AND p.Document = o.Document WHERE p.PetId = 2 AND p.OwnerID IS NULL; ... UPDATE p SET OwnerID = o.OwnerID FROM temp_pets p INNER JOIN temp_owners o ON p.Country = o.Country WHERE p.PetId = 3 AND p.OwnerID IS NULL;部分AND p.OwnerID IS NULL部分条款。

运行一批更新语句后，temp_pets表如下所示：

where

You can see a live demo on rextester.

但是，请注意，您拥有的条件越少，记录可能会从联接中返回，这使得更新更有可能不准确。例如，对于PetId 3，我有OwnerId 1，因为我唯一需要匹配记录的是PetID Address Zip Country Document OwnerName OwnerID Field1 Field2 1 123 5th st 12345 US test.csv John 5 NULL NULL 2 234 6th st 23456 US a.csv Alex 6 NULL NULL 3 345 7th st 34567 US b.csv Mike 1 NULL NUL列，这意味着它实际上可能是此示例数据中的每个Country，因为每个人在OwnerId列中都具有相同的值US 根据以下规则，我无能为力。

Answer 5

这可以不使用动态sql或循环。关键点在于用于匹配宠物和所有者的列是静态的。只有优先事项是动态的。但是，性能在很大程度上取决于您的数据。您必须自己测试并考虑您认为最好的方法。

下面的解决方案基本上找到了与任何给定宠物匹配的所有者。然后过滤所有者以仅包括匹配优先级1或1＆amp; 1的所有者。 2，或1＆amp; 2＆amp; 3，等等最后＆＃34;最佳＆＃34;找到匹配的所有者，并使用此值更新宠物表。

我已在查询中添加了一些解释性评论，但请随时询问是否有任何不明确的内容。

-- We start off by converting the priority values into int values that are suitable to add up to a bit array
-- I'll save those in a #Temp table to cut that piece of logic out of the final query
IF EXISTS(SELECT 1 FROM #TempBuilder)
BEGIN
    DROP TABLE #TempBuilder
END
SELECT 
    PetID, Field, MatchTo, 
    CASE [Priority] 
    WHEN 1 THEN 16 -- Priority one goes on the 16-bit (10000)
    WHEN 2 THEN 8 -- Priority two goes on the 8-bit (01000)
    WHEN 3 THEN 4 -- Priority three goes on the 4-bit (00100)
    WHEN 4 THEN 2 -- Priority four goes on the 2-bit (00010)
    WHEN 5 THEN 1 END AS [Priority] -- Priority five goes on the 1-bit (00001)
INTO #TempBuilder
FROM dbo.temp_builder;

-- Then we pivot the match priorities to be able to join them on our pets
WITH PivotedMatchPriorities AS (
    SELECT
        PetId,
        [Address], [Zip], [Country], [OwnerName], [Document]
    FROM (SELECT PetId, Field, [Priority] FROM #TempBuilder) tb
        PIVOT 
        (
            SUM([Priority])
            FOR [Field] IN ([Address], [Zip], [Country], [OwnerName], [Document])
        )
        AS PivotedMatchPriorities
),
-- Next we get (for each pet) all owners with ANY matching value
-- We want to filter the matching owners to find these that match priorities 1 (priority sum 10000, i.e. 16), 
    --- or match priorities 1 & 2 (priority sum 11000, i.e. 24)
    --- or match priorities 1 & 2 & 3 (priority sum 11100, i.e. 28)
    --- etc.
MatchingOwners AS (
    SELECT o.*,
        p.PetID,
        pmp.[Address] AS AddressPrio,
        pmp.Country AS CountryPrio,
        pmp.Zip AS ZipPrio,
        pmp.OwnerName AS OwnerPrio,
        pmp.Document AS DocumentPrio,
        CASE WHEN o.Addr = p.[Address] THEN ISNULL(pmp.[Address],0) ELSE 0 END
        + CASE WHEN o.Zip = p.Zip THEN ISNULL(pmp.Zip,0) ELSE 0 END
        + CASE WHEN o.Country = p.Country THEN ISNULL(pmp.Country,0) ELSE 0 END
        + CASE WHEN o.Document = p.Document THEN ISNULL(pmp.[Document],0) ELSE 0 END
        + CASE WHEN o.[Name] = p.OwnerName THEN ISNULL(pmp.OwnerName,0) ELSE 0 END AS MatchValue -- Calculate a match value for each matching owner
    FROM dbo.temp_pets p
        INNER JOIN dbo.temp_owners o 
            ON p.[Address] = o.Addr
            OR p.Country = o.Country
            OR p.Document = o.Document
            OR p.OwnerName = o.[Name]
            OR p.Zip = o.Zip
        INNER JOIN PivotedMatchPriorities pmp ON pmp.PetId = p.PetId
),
-- Now we can get all owners that match the pet, along with a match value for each owner.
-- We want to rank the matching owners for each pet to allow selecting the best ranked owner
-- Note: In the demo data there are multiple owners that match petId 3 equally well. We'll pick a random one in such cases.
RankedValidMatches AS (
    SELECT 
        PetID,
        OwnerID,
        MatchValue,
        ROW_NUMBER() OVER (PARTITION BY PetID ORDER BY MatchValue DESC) AS OwnerRank
    FROM MatchingOwners
    WHERE MatchValue IN (16, 24, 28, 30, 31)
)
-- Finally we can get the best valid match per pet
--SELECT * FROM RankedValidMatches WHERE OwnerRank = 1
-- Or we can update our pet table to reflect our results
UPDATE dbo.temp_pets
SET OwnerID = rvm.OwnerID
FROM dbo.temp_pets tp
    INNER JOIN RankedValidMatches rvm ON rvm.PetID = tp.PetID AND rvm.OwnerRank = 1

Answer 6

以下方法基于以下事实：选择不同组合的数量并命令列匹配，这是有限的，并且可能远远小于记录数。对于5列，组合总数为325，但由于不太可能使用每种可能的组合，实际数量可能小于100。与记录的数量（OP提到的> 1M）相比，尝试组合共享相同列的组合的宠物是值得的。

以下SQL脚本的特征：

没有动态SQL。
循环，但没有游标;迭代次数有限，并且不会与记录数成比例增长。
创建两个（索引的）帮助程序表。（请随意使它们成为临时表或表变量。）这大大加快了匹配过程（INNER JOIN），但它确实带来了填充表的一些开销。
只有简单的SQL结构（没有枢轴，没有填充FOR XML，甚至没有CTE）。
仅依赖于键列（PetID，OwnerID），优先级列和帮助程序表中的列的索引。不需要地址，邮政编码，国家，文件，名称上的索引。

乍一看，查询似乎总是过度杀戮（对OP提出的少量样本数据执行了47条SQL语句），但对于更大的表格，优势应该变得明显。最坏的情况时间复杂度应该是 O （ n log n ），这比许多替代方案要好得多。但当然它仍需要在实践中证明自己;我还没有使用大型数据集进行测试。

小提琴：http://sqlfiddle.com/#!18/53320/1

-- Adding indexes to OP's tables to optimize the queries that follow.
CREATE INDEX IX_PetID ON temp_builder (PetID)
CREATE INDEX IX_Priority ON temp_builder (Priority)
CREATE INDEX IX_PetID ON temp_pets (PetID)
CREATE INDEX IX_OwnerID ON temp_owners (OwnerID)

-- Helper table for pets. Each column has its own index.
CREATE TABLE PetKey (
    PetID int NOT NULL PRIMARY KEY CLUSTERED,
    KeyNames varchar(200) NOT NULL INDEX IX_KeyNames NONCLUSTERED,
    KeyValues varchar(900) NOT NULL INDEX IX_KeyValues NONCLUSTERED
)

-- Helper table for owners. Each column has its own index.
CREATE TABLE OwnerKey (
    OwnerID int NOT NULL PRIMARY KEY CLUSTERED,
    KeyValues varchar(900) NULL INDEX IX_KeyValues NONCLUSTERED
)

-- For every pet, create a record in table PetKey.
-- (Unless the pet already belongs to someone.)
INSERT INTO PetKey (PetID, KeyNames, KeyValues)
SELECT PetID, '', ''
FROM temp_pets
WHERE OwnerID IS NULL

-- For every owner, create a record in table OwnerKey.
INSERT INTO OwnerKey (OwnerID, KeyValues)
SELECT OwnerID, ''
FROM temp_owners

-- Populate columns KeyNames and KeyValues in table PetKey.
-- Lowest priority (i.e. highest number in column Priority) comes first.
-- We use CHAR(1) as a separator character; anything will do as long as it does not occur in any column values.
-- Example: when a pet has address as prio 1, zip as prio 2, then:
--    KeyNames = 'Zip' + CHAR(1) + 'Address' + CHAR(1)
--    KeyValues = '12345' + CHAR(1) + 'John' + CHAR(1)
-- NULL is replaced by CHAR(2); can be any value as long as it does not match any owner's value.
DECLARE @priority int = 1
WHILE EXISTS (SELECT * FROM temp_builder WHERE Priority = @priority)
BEGIN
    UPDATE pk
    SET KeyNames = b.Field + CHAR(1) + KeyNames,
        KeyValues = ISNULL(CASE b.Field
                               WHEN 'Address' THEN p.Address
                               WHEN 'Zip' THEN CAST(p.Zip AS varchar)
                               WHEN 'Country' THEN p.Country
                               WHEN 'Document' THEN p.Document
                               WHEN 'OwnerName' THEN p.OwnerName
                           END, CHAR(2)) +
                    CHAR(1) + KeyValues
    FROM PetKey pk
    INNER JOIN temp_pets p ON p.PetID = pk.PetID
    INNER JOIN temp_builder b ON b.PetID = pk.PetID
    WHERE b.Priority = @priority

    SET @priority = @priority + 1
END

-- Loop through all distinct key combinations.
DECLARE @maxKeyNames varchar(200), @namesToAdd varchar(200), @index int
SELECT @maxKeyNames = MAX(KeyNames) FROM PetKey
WHILE @maxKeyNames <> '' BEGIN
    -- Populate column KeyValues in table OwnerKey.
    -- The order of the values is determined by the column names listed in @maxKeyNames.
    UPDATE OwnerKey
    SET KeyValues = ''

    SET @namesToAdd = @maxKeyNames
    WHILE @namesToAdd <> '' BEGIN
        SET @index = CHARINDEX(CHAR(1), @namesToAdd)

        UPDATE ok
        SET KeyValues = KeyValues +
                        CASE LEFT(@namesToAdd, @index - 1)
                            WHEN 'Address' THEN o.Addr
                            WHEN 'Zip' THEN CAST(o.Zip AS varchar)
                            WHEN 'Country' THEN o.Country
                            WHEN 'Document' THEN o.Document
                            WHEN 'OwnerName' THEN o.Name
                        END +
                        CHAR(1)
        FROM OwnerKey ok
        INNER JOIN temp_owners o ON o.OwnerID = ok.OwnerID

        SET @namesToAdd = SUBSTRING(@namesToAdd, @index + 1, 200)
    END

    -- Match pets with owners, based on their KeyValues.
    UPDATE p
    SET OwnerID = (SELECT TOP 1 ok.OwnerID FROM OwnerKey ok WHERE ok.KeyValues = pk.KeyValues)
    FROM temp_pets p
    INNER JOIN PetKey pk ON pk.PetID = p.PetID
    WHERE pk.KeyNames = @maxKeyNames

    -- Pets that were successfully matched are removed from PetKey.
    DELETE FROM pk
    FROM PetKey pk
    INNER JOIN temp_pets p ON p.PetID = pk.PetID
    WHERE p.OwnerID IS NOT NULL

    -- For pets with no match, strip off the first (lowest priority) name and value.
    SET @namesToAdd = SUBSTRING(@maxKeyNames, CHARINDEX(CHAR(1), @maxKeyNames) + 1, 200)

    UPDATE pk
    SET KeyNames = @namesToAdd,
        KeyValues = SUBSTRING(KeyValues, CHARINDEX(CHAR(1), KeyValues) + 1, 900)
    FROM PetKey pk
    INNER JOIN temp_pets p ON p.PetID = pk.PetID
    WHERE pk.KeyNames = @maxKeyNames

    -- Next key combination.    
    SELECT @maxKeyNames = MAX(KeyNames) FROM PetKey
END

Answer 7

我使用UNPIVOT编写了另一个版本，但是对行进行排名并以更简单的方式过滤

;with
-- r: rules table
r as (select * from temp_builder),
-- o0: owners table with all fields unpivotable (varchar)
o0 as (SELECT [OwnerID], [Addr], CAST([Zip] AS VARCHAR(100)) AS [Zip], [Country], [Document], [Name] FROM temp_owners ),
-- o: owners table unpivoted
o as (
    SELECT * FROM o0 
    UNPIVOT (FieldValue FOR Field IN ([Addr], [Zip], [Country], [Document], [Name])) AS p
),
-- p0: pets table with all fields unpivotable (varchar)
p0 as (SELECT [PetID], [Address], CAST([Zip] AS VARCHAR(100)) AS [Zip], [Country], [Document], [OwnerName] FROM temp_pets),
-- p: petstable unpivoted
p as (
    SELECT * FROM p0
    UNPIVOT (FieldValue FOR Field IN ([Address], [Zip], [Country], [Document], [OwnerName])) AS p
),
-- t: join up all data and keep only matching priority
d as (
    select petid, ownerid, priority 
    from (
        select r.*, o.ownerid, ROW_NUMBER() over (partition by r.petid, o.ownerid order by r.petid, o.ownerid, priority) calc_priority
        from r
        join p on (r.field = p.field) and (p.petid = r.petid)
        join o on (r.matchto = o.field) and (p.fieldvalue=o.fieldvalue) 
    ) x
    where calc_priority=priority
),
-- g: group by the matching rows to know the best priority reached for each pet
g as (
    select petid, max(priority) max_priority
    from d
    group by petid
)
-- output only the rows with best priority
select d.*
from d
join g on d.petid = g.petid and d.priority = g.max_priority
order by petid, ownerid, priority

这个版本的性能不比@EdmondQuinton高（我投票给他），我的速度慢了5％，但我认为非专业用户更容易理解和维护。

Answer 8

我会采用稍微不同的方法，而不是存储要匹配的列，您可以存储要执行的查询：

create table builder
(
    PetID int not null,
    Query varchar(max)
)

INSERT INTO builder
VALUES (1, 'SELECT TOP 1 *
FROM pets
INNER JOIN Owners
    ON Owners.Name = pets.OwnerName 
WHERE petId = 1
ORDER BY 
    CASE WHEN Owners.Country = pets.Country THEN 0 ELSE 1 END,
    CASE WHEN Owners.Zip = pets.Zip THEN 0 ELSE 1 END,
    CASE WHEN Owners.Addr = pets.Address THEN 0 ELSE 1 END'),
(2, 'SELECT TOP 1 *
FROM pets
INNER JOIN Owners
    ON Owners.Name = pets.OwnerName 
WHERE petId = 2
ORDER BY 
    CASE WHEN Owners.Document = pets.Document THEN 0 ELSE 1 END,
    CASE WHEN Owners.Name = pets.OwnerName THEN 0 ELSE 1 END,
    CASE WHEN Owners.Zip = pets.Zip THEN 0 ELSE 1 END'),
(3, 'SELECT TOP 1 *
FROM pets
INNER JOIN Owners
    ON Owners.Name = pets.OwnerName 
WHERE petId = 3
ORDER BY 
    CASE WHEN Owners.Country = pets.Country THEN 0 ELSE 1 END
')

create table pets
(
    PetID int null,
    Address varchar(100) null,
    Zip int null,
    Country varchar(100) null,
    Document varchar(100) null,
    OwnerName varchar(100) null,
    OwnerID int null,
    Field1 bit null,
    Field2 bit null
)

insert into pets values
(1, '123 5th st', 12345, 'US', 'test.csv', 'John', NULL, NULL, NULL),
(2, '234 6th st', 23456, 'US', 'a.csv', 'Alex', NULL, NULL, NULL),
(3, '345 7th st', 34567, 'US', 'b.csv', 'Mike', NULL, NULL, NULL)

create table owners
(
    OwnerID int null,
    Addr varchar(100) null,
    Zip int null,
    Country varchar(100) null,
    Document varchar(100) null,
    Name varchar(100) null,
    OtherField bit null,
    OtherField2 bit null,
)

insert into owners values
(1, '456 8th st',  45678, 'US', 'c.csv', 'Mike',  NULL, NULL),
(2, '678 9th st',  45678, 'US', 'b.csv', 'John',  NULL, NULL),
(3, '890 10th st', 45678, 'US', 'b.csv', 'Alex',  NULL, NULL),
(4, '901 11th st', 23456, 'US', 'b.csv', 'Alex',  NULL, NULL),
(5, '234 5th st',  12345, 'US', 'b.csv', 'John',  NULL, NULL),
(6, '123 5th st',  45678, 'US', 'a.csv', 'John',  NULL, NULL)

现在找到特定宠物的匹配所有者，您只需从表中找到该查询并执行它：

DECLARE @query varchar(max)
SELECT TOP 1 @query = query
FROM builder
WHERE petId =1

EXEC (@query)

Answer 9

考虑到这一点，这是一个严格解决您问题的答案

按照规则提出没有循环，没有游标，没有动态sql
并且还严格考虑您的问题，因此这不是一般解决方案，它非常针对您的问题以及列

TESTDATA

declare @Pets table 
(
    PetID int null,
    Address varchar(100) null,
    Zip int null,
    Country varchar(100) null,
    Document varchar(100) null,
    OwnerName varchar(100) null,
    OwnerID int null,
    Field1 bit null,
    Field2 bit null
)

insert into @Pets values
(1, '123 5th st', 12345, 'US', 'test.csv', 'John', NULL, NULL, NULL),
(2, '234 6th st', 23456, 'US', 'a.csv', 'Alex', NULL, NULL, NULL),
(3, '345 7th st', 34567, 'US', 'b.csv', 'Mike', NULL, NULL, NULL)

declare @owners table
(
    OwnerID int null,
    Addr varchar(100) null,
    Zip int null,
    Country varchar(100) null,
    Document varchar(100) null,
    Name varchar(100) null,
    OtherField bit null,
    OtherField2 bit null
)

insert into @owners values
(1, '456 8th st',  45678, 'US', 'c.csv', 'Mike',  NULL, NULL),
(2, '678 9th st',  45678, 'US', 'b.csv', 'John',  NULL, NULL),
(3, '890 10th st', 45678, 'US', 'b.csv', 'Alex',  NULL, NULL),
(4, '901 11th st', 23456, 'US', 'b.csv', 'Alex',  NULL, NULL),
(5, '234 5th st',  12345, 'US', 'b.csv', 'John',  NULL, NULL),
(6, '123 5th st',  45678, 'US', 'a.csv', 'John',  NULL, NULL)

declare @builder table  
(
    PetID int not null,
    Field varchar(30) not null,
    MatchTo varchar(30) not null,
    Priority int not null
)

insert into @builder values
(1,'Address', 'Addr',4),
(1,'Zip', 'Zip', 3),
(1,'Country', 'Country', 2),
(1,'OwnerName', 'Name',1),
(2,'Zip', 'Zip',3),
(2,'OwnerName','Name', 2),
(2,'Document', 'Document', 1),
(3,'Country', 'Country', 1)

解决问题的代码

select distinct p.PetID, min(o.OwnerID) as ownerID from @pets p
inner join @builder b on p.PetID = b.PetID
inner join @owners o on 
( 
   (case when b.Field = 'Address' and b.Priority = 1 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 1 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 1 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 1 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 1 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 1 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 1 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 1 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 1 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 1 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 2 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 2 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 2 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 2 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 2 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 2 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 2 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 2 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 2 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 2 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 3 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 3 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 3 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 3 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 3 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 3 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 3 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 3 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 3 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 3 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 4 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 4 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 4 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 4 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 4 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 4 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 4 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 4 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 4 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 4 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 5 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 5 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 5 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 5 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 5 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 5 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 5 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 5 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 5 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 5 then o.Document else '-1' end)                    
)
group by p.PetID

union
--------------------------

select distinct p.PetID, min(o.OwnerID) as ownerID from @pets p
inner join @builder b on p.PetID = b.PetID
inner join @owners o on 
( 
   (case when b.Field = 'Address' and b.Priority = 1 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 1 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 1 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 1 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 1 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 1 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 1 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 1 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 1 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 1 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 2 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 2 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 2 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 2 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 2 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 2 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 2 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 2 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 2 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 2 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 3 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 3 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 3 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 3 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 3 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 3 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 3 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 3 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 3 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 3 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 4 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 4 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 4 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 4 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 4 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 4 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 4 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 4 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 4 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 4 then o.Document else '-1' end)                    
)
group by p.PetID

union
--------------------------

select distinct p.PetID, min(o.OwnerID) as ownerID from @pets p
inner join @builder b on p.PetID = b.PetID
inner join @owners o on 
( 
   (case when b.Field = 'Address' and b.Priority = 1 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 1 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 1 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 1 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 1 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 1 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 1 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 1 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 1 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 1 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 2 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 2 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 2 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 2 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 2 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 2 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 2 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 2 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 2 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 2 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 3 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 3 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 3 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 3 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 3 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 3 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 3 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 3 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 3 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 3 then o.Document else '-1' end)                    
)
group by p.PetID

union
------------------------

select distinct p.PetID, min(o.OwnerID) as ownerID from @pets p
inner join @builder b on p.PetID = b.PetID
inner join @owners o on 
( 
   (case when b.Field = 'Address' and b.Priority = 1 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 1 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 1 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 1 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 1 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 1 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 1 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 1 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 1 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 1 then o.Document else '-1' end)                    
)
AND
( 
   (case when b.Field = 'Address' and b.Priority = 2 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 2 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 2 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 2 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 2 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 2 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 2 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 2 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 2 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 2 then o.Document else '-1' end)                    
)
group by p.PetID

union
------------------------

select distinct p.PetID, min(o.OwnerID) as ownerID from @pets p
inner join @builder b on p.PetID = b.PetID
inner join @owners o on 
( 
   (case when b.Field = 'Address' and b.Priority = 1 then p.Address else '0' end) = (case when b.MatchTo = 'Addr' and b.Priority = 1 then o.Addr else '-1' end)                  
or (case when b.Field = 'Zip' and b.Priority = 1 then p.Zip else '0' end) = (case when b.MatchTo = 'Zip' and b.Priority = 1 then o.Zip else '-1' end)                    
or (case when b.Field = 'Country' and b.Priority = 1 then p.Country else '0' end) = (case when b.MatchTo = 'Country' and b.Priority = 1 then o.Country else '-1' end)                    
or (case when b.Field = 'OwnerName' and b.Priority = 1 then p.OwnerName else '0' end) = (case when b.MatchTo = 'Name' and b.Priority = 1 then o.Name else '-1' end)                  
or (case when b.Field = 'Document' and b.Priority = 1 then p.Document else '0' end) = (case when b.MatchTo = 'Document' and b.Priority = 1 then o.Document else '-1' end)                    
)
group by p.PetID

结果

PetID   OwnerID
1       2
2       6
3       1

Answer 10

如果您正在寻找一个没有union的简单解决方案，循环或游标或下面的动态SQL工作正常。

SQL小提琴：http://sqlfiddle.com/#!18/10982/41

select PetID ,COALESCE(
 (select  top 1 OwnerID from temp_owners
     where Zip = pets.Zip 
     and Name = pets.OwnerName
     and Document = pets.Document) ,
     (select top 1 OwnerID from temp_owners where
         Name = pets.OwnerName 
         and Document = pets.Document)  ,
         (select top 1 OwnerID from temp_owners where
          Document = pets.Document)  ) OwnerId
       from 
temp_pets pets

结果：

PetID   OwnerId
1       (null)
2       6
3       2

根据动态列查找匹配的记录

10 个答案:

TESTDATA

解决问题的代码

结果