Question

考虑这个CTE

;WITH Columns AS 
(
    SELECT object_id AS TableId, Name AS ColumnName 
    FROM SYS.columns
), 
Tables AS 
(
    SELECT S.NAME AS SchemaName, T.NAME AS TableName, object_id AS TableId
    FROM sys.tables T
    INNER JOIN  sys.schemas S ON S.schema_id = T.schema_id
)
SELECT T.SchemaName, T.TableName, C.ColumnName
FROM Tables T
INNER JOIN Columns C ON T.TableId = C.TableId

我想要做的是将列的结果限制为前三个（例如按字母顺序排列）

所以如果我有1个模式（例如dbo）和2个表TableX＆amp; TableY有4个cols，每个ColA，ColB，ColC，ColD我的结果都是

之类的东西

  dbo   TableX    ColA
  dbo   TableX    ColB
  dbo   TableX    ColC
  dbo   TableY    ColA
  dbo   TableY    ColB
  dbo   TableY    ColC

schema_a

Answer 1

看起来我找到了答案： - ）

Select Top row of 2nd table in SQL Join

;WITH Columns AS 
(
    SELECT 
        row_number() over (partition by object_id ORDER BY Name DESC) as RowNumber,
        object_id AS TableId, 
        Name AS ColumnName 
    FROM SYS.columns
), 
Tables AS 
(
    SELECT 
        S.NAME AS SchemaName, 
        T.NAME AS TableName, object_id AS TableId
    FROM sys.tables T
    INNER JOIN  sys.schemas S ON S.schema_id = T.schema_id
)
SELECT T.SchemaName, T.TableName, C.RowNumber, C.ColumnName
FROM Tables T
INNER JOIN Columns C ON T.TableId = C.TableId
where RowNumber BETWEEN 1 AND 3

限制SQL仅加入连接表中的前3项

1 个答案: