书上看到一段代码求解

[xuyuchends]

SET NOCOUNT ON;
USE temp;
GO
IF OBJECT_ID('dbo.T1') IS NOT NULL
  DROP TABLE dbo.T1;
GO
CREATE TABLE dbo.T1
(
  keycol  INT NOT NULL PRIMARY KEY,
  datacol VARCHAR(10) NOT NULL
);
IF OBJECT_ID('dbo.Sequence') IS NOT NULL
  DROP TABLE dbo.Sequence;
GO
CREATE TABLE dbo.Sequence(val INT NOT NULL);
INSERT INTO dbo.Sequence VALUES(0);
--创建触发器
CREATE TRIGGER trg_T1_ioi_assign_key ON dbo.T1 INSTEAD OF INSERT
AS

DECLARE @rc AS INT, @key AS INT;
SET @rc = @@rowcount;

IF @rc = 0 RETURN; -- if 0 affected rows, exit

-- Update sequence
UPDATE dbo.Sequence SET @key = val, val = val + @rc;

INSERT INTO dbo.T1(keycol, datacol)
  SELECT @key + ROW_NUMBER() OVER(ORDER BY const), datacol
  FROM (SELECT 1 AS const, datacol FROM inserted) AS I;
GO

请问SELECT 1 AS const, datacol FROM inserted这句是什么意思，请解释一下，谢谢

[SQL77]

inserted

查帮助了解一下这个虚拟表

[xuyuchends]

傻掉了，我看懂了。把1赋值给 const。改头像了嘛，分都给你吧

[SQL77]

[Quote=引用 2 楼 xuyuchends 的回复:]
傻掉了，我看懂了。把1赋值给 const。改头像了嘛，分都给你吧
[/Quote]
这个就是一个 列名AS 列标题的写法而已吧,还以为INSERTED问题