Question

我目前正在尝试创建一个可以显示新行信息并删除重复的SQL报告。

为了这个例子，我有一个列（car）从tableA获取一个字段，然后链接到tableB（颜色）。类似下表。

-----------------------------
|Car (TableA)|Colour(TableB)|
-----------------------------
|CarA        |Blue          |
|CarA        |Black         |
|CarA        |Yellow        |
|CarB        |Purple        |
|CarB        |Orange        |
|CarB        |Black         |
-----------------------------

相反，我试图让我的数据显示一些这样的东西：

-----------------------------
|Car (TableA)|Colour(TableB)|
-----------------------------
|CarA        |Blue          |
|            |Black         |
|            |Yellow        |
|            |              |
|CarB        |Purple        |
|            |Orange        |
|            |Black         |
-----------------------------

Answer 1

这应该是诀窍：

declare @tbl as table (
    car varchar(10)
    ,brand varchar(10)
    ,colour varchar(10)
)

insert into @tbl values ('CarA', 'Tesla', 'Blue')
insert into @tbl values ('CarA', 'Tesla', 'Black')
insert into @tbl values ('CarA', 'Tesla', 'Yellow')
insert into @tbl values ('CarB', 'Kia', 'Purple')
insert into @tbl values ('CarB', 'Kia', 'Orange')
insert into @tbl values ('CarB', 'Kia', 'Black')
insert into @tbl values ('CarC', 'Ford', 'Green')

SELECT
    CASE WHEN rn > 1 THEN '' ELSE car END AS car
    ,colour
FROM (
    SELECT
        car
        ,colour
        ,ROW_NUMBER() OVER (PARTITION BY car ORDER BY car, colour ASC) rn
    FROM @tbl
) tbl

<强>更新

说brand和car之间有colour：

SELECT
    CASE WHEN rn > 1 THEN '' ELSE car END AS car
    ,CASE WHEN rn > 1 THEN '' ELSE brand END AS brand
    ,colour
FROM (
    SELECT
        car
        ,brand
        ,colour
        ,ROW_NUMBER() OVER (PARTITION BY car, brand ORDER BY car, colour ASC) rn
    FROM @tbl
) tbl

组织数据以删除某些列中的重复项

1 个答案: