基于存储搜索参数的 SQL Server 动态搜索

Question

我必须创建一个动态搜索。搜索条件存储在表中，存储记录有一个主表。这是结构：

--Main Table. This table stores records of a user. Basically we store files in this table. Each file is associated with a single city.
DECLARE @Records TABLE(
[RecordId] INT IDENTITY(1,1),
[FileName] VARCHAR(100),
[OwnerId] INT,
[CityId] INT
)
INSERT INTO @Records
SELECT 'A', 100, 101 UNION
SELECT 'B', 100, 102 UNION
SELECT 'C', 100, 103 UNION
SELECT 'D', 100, 104

--The next table is used to associate a file with multiple friends.
DECLARE @FriendRecords TABLE
(
[Id] INT IDENTITY(1,1),
[RecordId] INT,
[FriendId] INT
)
INSERT INTO @FriendRecords
SELECT 1, 201 UNION --File '1' is associated with 'FriendId' 201
SELECT 1, 202 UNION --File '1' is associated with 'FriendId' 202
SELECT 2, 201 UNION --File '2' is associated with 'FriendId' 201
SELECT 3, 202       --File '3' is associated with 'FriendId' 202

--The following table is used to create a criteria for user.
DECLARE @Criteria TABLE
(
[CriteriaId] INT IDENTITY(1,1),
[CriteriaName] VARCHAR(50),
[OwnerId] INT
)
INSERT INTO @Criteria
SELECT 'SampleCriteria', 100 --Criteria created by user 100

--The following table is used to store cities that needs to be searched in 'Records' table for owner of criteriaId '1'.
DECLARE @CriteriaCities TABLE(
[CriteriaCityId] INT IDENTITY(1,1),
[CriteriaId] INT, 
[CityId] INT
)
INSERT INTO @CriteriaCities
SELECT 1, 101 UNION
SELECT 1, 102 UNION
SELECT 1, 103 

--The following table is used to store friend that needs to be searched in 'FriendsRecords' table for owner of criteriaId '1'.
DECLARE @CriteriaFriend TABLE(
[CriteriaCityId] INT IDENTITY(1,1),
[CriteriaId] INT, 
[FriendId] INT
)
INSERT INTO @CriteriaFriend
SELECT 1, 202;

基本上，用户可以创建一个条件（@Criteria 表）并存储搜索参数（@CriteriaCities 和@CriteriaFriend 表）。要求是根据存储的条件获取文件。我正在寻找的查询应该从@Records 表中返回具有cityIds 101、102&103 AND FriendId '201' 的记录。结果只是@Records 表中的“C”。如果我在所有表上创建左连接，我也会获得 ownerId '100' 的其他记录。如果我在表中包含一个内部联接，如果@CriteriaCities 或@CriteriaFriend 表中没有条件条目，我将不会得到任何记录。根据链接表（@CriteriaCities，@CriteriaFriend）中存在的记录搜索主表中记录的查询应该是什么？如果搜索参数未存储在这些表中，则不应在这些表之间创建连接。

Answer 1

我不确定您是否完全理解了您的逻辑，因为根据我的评论，您的问题不太有意义，但如果我遵循您所说的作为您的规则，您可以使用以下 select 语句来获取您的数据。不过，我不确定您将如何通过您正在搜索的标准，因为您尚未解释这部分流程的工作原理：

-- Count the records in each criteria table.
declare @CriteriaCitiesCount int = (select count(1) from @CriteriaCities);
declare @CriteriaFriendCount int = (select count(1) from @CriteriaFriend);


select *
from @Records r
    left join @CriteriaCities cc
        on(r.CityId = cc.CityId)
    left join @FriendRecords f
        on(r.RecordId = f.RecordId)
    left join @CriteriaFriend cf
        on(f.FriendId = cf.FriendId)
where (@CriteriaCitiesCount = 0        -- Only return records where we aren't filtering,
        or cc.CityId is not null       -- Or we are filtering and we get a match.
        )
    and (@CriteriaFriendCount = 0
        or cf.FriendId is not null
        );

Answer 2

抱歉，我无法理解您的输出。 为什么你应该只得到 FileName C ？

试试类似的，

;With CTE as
(
select cc.CityId,cf.FriendId    
from @Criteria C
inner join @CriteriaCities CC
on c.CriteriaId=cc.CriteriaId
inner join @CriteriaFriend CF  
on c.CriteriaId=cf.CriteriaId
where c.OwnerId=@ownerid
)

select *
from @Records R
inner join @FriendRecords FR
on r.RecordId=fr.RecordId
where EXISTS(
select cityid from cte c where r.CityId=c.cityid and c.FriendId=fr.FriendId
)