Move row from one table to another?

Question

I have two tables with the same column definitions. I need to move (not copy) a row from one table to another. Before I go off and use INSERT INTO/DELETE (in a transaction), is there a smarter way?

SQL Server 2005

Solution

for SQL Server 2005 and up, try the OUTPUT Clause (Transact-SQL) clause:

DELETE OldTable
  OUTPUT DELETED.col1, DELETED.col2...
      INTO NewTable
  WHERE ID=...

Working example:

DECLARE @OldTable table(col1 int, col2    varchar(5), col3 char(5), col4     datetime)
DECLARE @NewTable table(col1 int, column2 varchar(5), col3 int    , col_date char(23), extravalue int, othervalue varchar(5))
INSERT @OldTable VALUES (1 , 'AAA' ,'A'  ,'1/1/2010'           )
INSERT @OldTable VALUES (2 , 'BBB' ,'12' ,'2010-02-02 10:11:22')
INSERT @OldTable VALUES (3 , 'CCC' ,null ,null                 )
INSERT @OldTable VALUES (4 , 'B'   ,'bb' ,'2010-03-02'         )

DELETE @OldTable
    OUTPUT DELETED.col1
          ,DELETED.col2
          ,CASE
               WHEN ISNUMERIC(DELETED.col3)=1 THEN DELETED.col3 
               ELSE NULL END
          ,DELETED.col4
          ,CONVERT(varchar(5),DELETED.col1)+'!!'
        INTO @NewTable (col1, column2, col3, col_date, othervalue)
    OUTPUT 'Rows Deleted: ', DELETED.* --this line returns a result set shown in the OUTPUT below
    WHERE col1 IN (2,4)

SELECT * FROM @NewTable

OUTPUT:

               col1        col2  col3  col4
-------------- ----------- ----- ----- -----------------------
Rows Deleted:  2           BBB   12    2010-02-02 10:11:22.000
Rows Deleted:  4           B     bb    2010-03-02 00:00:00.000

(2 row(s) affected)

col1        column2 col3        col_date                extravalue  othervalue
----------- ------- ----------- ----------------------- ----------- ----------
2           BBB     12          Feb  2 2010 10:11AM     NULL        2!!
4           B       NULL        Mar  2 2010 12:00AM     NULL        4!!

(2 row(s) affected)

Comments

[Daniel Vassallo]

@KM: +1. I was not aware of this. Would you recommend this method over INSERT and DELETE?

[KM.]

I would use this over an INSERT and a DELETE every time, SQL Server can probably optimize it better and it guarantees you INSERT and DELETE only the same rows, no more and no less.

[lance]

This is one statement, so... no transaction necessary, I guess?

[KM.]

OP is using SQL Server 2005, so the OUTPUT Clause (Transact-SQL) can do it in a single command, see my answer...

[KM.]

OP is using SQL Server 2005, so the OUTPUT Clause (Transact-SQL) can do it in a single command, see my answer...

[KM.]

@lance, unless you have other database changes that you want to tie to this command, then no.

[KM.]

@lance, I've added a working example, if that doesn't answer your question, provide more specifics on the columns in the tables that are having questions about.

[lance]

I'm in great shape. It was an absolute long shot, my asking this question. I just thought I'd ask the smart people before doing "what I know". It's so satisfying getting such a great answer, and it's even more satisfying seeing the multiple other people who thought as I did and have learned this "new" technique from my question. Thanks so very much.

[joshmax]

@KM. This topic is a bit old, but if you need to move the row w/o one of the columns and add in a new column, would you still suggest using this?

[KM.]

@Max, If you need to capture deleted rows, there is no better way than using OUTPUT. If you need another column I'd UPDATE and join it on after having the populated the rows with the DELETE OUTPUT.