sql-server - 当数据不存在时，T-SQL 添加带零的行

Question

我知道这个问题已被回答过几次，但我仍然无法添加额外的行，而数据在数据存在之前并不存在。

DECLARE @Test TABLE 

(
ID NVARCHAR(10)
,Number INT

)
INSERT INTO @Test VALUES ('TG32',6)
INSERT INTO @Test VALUES ('TG32',6)
INSERT INTO @Test VALUES ('TG32',6)
INSERT INTO @Test VALUES ('TG32',2)
INSERT INTO @Test VALUES ('QD65',2)
INSERT INTO @Test VALUES ('QD65',3)
INSERT INTO @Test VALUES ('QD65',3)
INSERT INTO @Test VALUES ('HT76',7)
INSERT INTO @Test VALUES ('HT76',1)
INSERT INTO @Test VALUES ('HT76',5)

 SELECT CASE WHEN ID = 'TG32' THEN 'Hats'
            WHEN ID =  'QD65' THEN 'Coats'
            WHEN ID =  'HT76' THEN 'Shoes'
            WHEN ID =   'WR52' THEN 'Shirts' END
            , Number


 FROM @Test

我试图在结果中获取额外的一行，显示“衬衫 0”，而 ID WR52 没有数据，直到有为止？

Answer 1

试试这个

DECLARE @Test TABLE 
(
ID NVARCHAR(10)
,Number INT

)
INSERT INTO @Test VALUES ('TG32',6)
INSERT INTO @Test VALUES ('TG32',6)
INSERT INTO @Test VALUES ('TG32',6)
INSERT INTO @Test VALUES ('TG32',2)
INSERT INTO @Test VALUES ('QD65',2)
INSERT INTO @Test VALUES ('QD65',3)
INSERT INTO @Test VALUES ('QD65',3)
INSERT INTO @Test VALUES ('HT76',7)
INSERT INTO @Test VALUES ('HT76',1)
INSERT INTO @Test VALUES ('HT76',5)

--
SELECT CASE WHEN ID = 'TG32' THEN 'Hats'
            WHEN ID =  'QD65' THEN 'Coats'
            WHEN ID =  'HT76' THEN 'Shoes'
            WHEN ID =   'WR52' THEN 'Shirts' END
            , Number
FROM @Test

UNION ALL

SELECT 'Shirts', 0
WHERE
    NOT EXISTS
    (
        SELECT TOP 1 1 FROM @Test
        WHERE
            ID = 'WR52'
    )

UNION ALL

SELECT 'Hats', 0
WHERE
    NOT EXISTS
    (
        SELECT TOP 1 1 FROM @Test
        WHERE
            ID = 'TG32'
    )


UNION ALL

SELECT 'Coats', 0
WHERE
    NOT EXISTS
    (
        SELECT TOP 1 1 FROM @Test
        WHERE
            ID = 'QD65'
    )

UNION ALL

SELECT 'Shoes', 0
WHERE
    NOT EXISTS
    (
        SELECT TOP 1 1 FROM @Test
        WHERE
            ID = 'HT76'
    )