Sql 根据列值形成查询

我使用的是sql server 2012，我有一个如下表：

FieldName     FieldValue
DivisionId    1
DivisionId    2
DivisionId    3
CompanyId     2
CompanyId     3
LocationId    1 

我想要的是连接列并形成一个where子句查询，如下所示

(DivisionId=1 OR DivisionId=2 OR DivisionId=3) AND
(CompanyId=2 OR CompanyId=3) AND
(LocationId = 1)

我能弄明白的是，我需要像这样连接列和值

DECLARE @Query VARCHAR(MAX)

SELECT @Query =
ISNULL(@Query,'') + IIF(@Query IS NOT NULL, ' AND ', '') + CONCAT(DF.FieldName,'=',DA.FieldValue)
FROM TABLE

SELECT @Query;

---

但此代码将无法处理或处理条件。

请尝试以下解决方案：

DECLARE @eav TABLE (
    FieldName       NVARCHAR(128) NOT NULL,
    FieldValue      VARCHAR(50) NOT NULL
)
INSERT  @eav (FieldName, FieldValue) 
SELECT 'DivisionId', 1 UNION ALL
SELECT 'DivisionId', 2 UNION ALL
SELECT 'DivisionId', 3 UNION ALL
SELECT 'CompanyId ', 2 UNION ALL
SELECT 'CompanyId ', 3 UNION ALL
SELECT 'LocationId', 1 

DECLARE @Predicate NVARCHAR(MAX) = N''
SELECT @Predicate = @Predicate
        + CASE WHEN rn_asc = 1 THEN ' AND ' + FieldName + ' IN (' + LTRIM(FieldValue) ELSE '' END
        + CASE WHEN rn_asc > 1 THEN ', ' + LTRIM(FieldValue) ELSE '' END
        + CASE WHEN rn_desc = 1 THEN ') ' ELSE '' END
FROM (
    SELECT  *, 
            rn_asc = ROW_NUMBER() OVER(PARTITION BY x.FieldName ORDER BY x.FieldValue),
            rn_desc= ROW_NUMBER() OVER(PARTITION BY x.FieldName ORDER BY x.FieldValue DESC)
    FROM    @eav x
) y
ORDER BY FieldName, FieldValue
SELECT @Predicate = STUFF(@Predicate, 1, 5, '')
SELECT @Predicate
-- Results: CompanyId  IN (2, 3)  AND DivisionId IN (1, 2, 3)  AND LocationId IN (1) 

然后，您可以使用

@谓词

创建动态SQL

SELECT

语句（例如）

---

首先为什么要使用动态sql？在大多数情况下，动态sql可以也应该被禁用。对，但根据要求，我必须使用它。现在别无选择

DECLARE @SqlStatement NVARCHAR(MAX)
SET @SqlStatement = 'SELECT ... FROM dbo.Table1 WHERE ' + @Predicate
EXEC sp_executesql @SqlStatement