Tuesday, March 6, 2012

Adding new columns to all tables using a script

Hi, I'm trying to add a modified datetime and userid to all 72 tables in my
SQL 2000 database. I have the script to do one table, and a cursor, but it
won't run across all tables. Any help would be appreciated. Thanks...

DECLARE @.tName varchar(40)
DECLARE C1 CURSOR FOR
select name from sysobjects where type = 'U'
OPEN C1
FETCH NEXT FROM C1 INTO @.tName
-- Check @.@.FETCH_STATUS to see if there are any more rows to fetch
WHILE @.@.FETCH_STATUS = 0
BEGIN
-- This is executed as long as the previous fetch succeeds
BEGIN TRANSACTION
SET QUOTED_IDENTIFIER ON
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
SET ARITHABORT ON
SET NUMERIC_ROUNDABORT OFF
SET CONCAT_NULL_YIELDS_NULL ON
SET ANSI_NULLS ON
SET ANSI_PADDING ON
SET ANSI_WARNINGS ON
COMMIT
BEGIN TRANSACTION
ALTER TABLE @.tName ADD
ModifiedDT datetime NULL,
ModifiedUserID int NULL
GO
COMMIT
FETCH NEXT FROM C1
END
CLOSE C1
DEALLOCATE C1
GOHi

As this is not production code then you may want to check out the
undocumented sp_MSforeachtable

http://groups.google.co.uk/groups?h...2%40tkmsftngp03

http://groups.google.co.uk/groups?h...man%40127.0.0.1

John

"Paul" <psampson@.uecomm.com.au> wrote in message
news:1061944796.500758@.proxy.uecomm.net.au...
> Hi, I'm trying to add a modified datetime and userid to all 72 tables in
my
> SQL 2000 database. I have the script to do one table, and a cursor, but it
> won't run across all tables. Any help would be appreciated. Thanks...
> DECLARE @.tName varchar(40)
> DECLARE C1 CURSOR FOR
> select name from sysobjects where type = 'U'
> OPEN C1
> FETCH NEXT FROM C1 INTO @.tName
> -- Check @.@.FETCH_STATUS to see if there are any more rows to fetch
> WHILE @.@.FETCH_STATUS = 0
> BEGIN
> -- This is executed as long as the previous fetch succeeds
> BEGIN TRANSACTION
> SET QUOTED_IDENTIFIER ON
> SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
> SET ARITHABORT ON
> SET NUMERIC_ROUNDABORT OFF
> SET CONCAT_NULL_YIELDS_NULL ON
> SET ANSI_NULLS ON
> SET ANSI_PADDING ON
> SET ANSI_WARNINGS ON
> COMMIT
> BEGIN TRANSACTION
> ALTER TABLE @.tName ADD
> ModifiedDT datetime NULL,
> ModifiedUserID int NULL
> GO
> COMMIT
> FETCH NEXT FROM C1
> END
> CLOSE C1
> DEALLOCATE C1
> GO|||Paul (psampson@.uecomm.com.au) writes:
> Hi, I'm trying to add a modified datetime and userid to all 72 tables in
> my SQL 2000 database. I have the script to do one table, and a cursor,
> but it won't run across all tables. Any help would be appreciated.

There are a number of errors in your script:

> DECLARE @.tName varchar(40)
> DECLARE C1 CURSOR FOR

While not an error, I recommend that you make your cursors INSENSITIVE
as a matter of routine. The default keyset-driven cursors can sometimes
give nasty surprises.

> select name from sysobjects where type = 'U'
> OPEN C1
> FETCH NEXT FROM C1 INTO @.tName
> -- Check @.@.FETCH_STATUS to see if there are any more rows to fetch
> WHILE @.@.FETCH_STATUS = 0

I recommend that you write cursor loops as

OPEN cur
WHILE 1 = 1
BEGIN
FETCH cur INTO @.var1, @.var2...
IF @.@.fetch_status <> 0
BREAK
-- Real job follows here.
END
DEALLOCATE cur

By only having one FETCH statement you make your code safer, because it's
easy to change the SELECT statement, and the new column to the first
FETCH, but forget the second, which may be the screens below.

> BEGIN TRANSACTION
> SET QUOTED_IDENTIFIER ON
> SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
> SET ARITHABORT ON
> SET NUMERIC_ROUNDABORT OFF
> SET CONCAT_NULL_YIELDS_NULL ON
> SET ANSI_NULLS ON
> SET ANSI_PADDING ON
> SET ANSI_WARNINGS ON
> COMMIT

There is no point in executing the SET statements in the loop, and
there is no point to make this a transaction. Not that it is wrong
either.

> BEGIN TRANSACTION
> ALTER TABLE @.tName ADD
> ModifiedDT datetime NULL,
> ModifiedUserID int NULL
> GO

Here are two serious flaws: ALTER TABLE does not accept a variable.
You need to use dynamic SQL for this. (Or sp_MSforeachtable.)

And the GO there is completely out of place. GO is not an SQL command,
but an instruction to the query tool to separate the commands into
different batches. Thus, this batch will fail with a compilation
error, because the BEGIN after WHILE does not have an END.

> FETCH NEXT FROM C1

And if you thought what I said about FETCH above was silly, look here!
Here you don't insert into a variable, but produce a result set.

--
Erland Sommarskog, SQL Server MVP, sommar@.algonet.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp|||Thanks John, I'll check it out

"John Bell" <jbellnewsposts@.hotmail.com> wrote in message
news:3f4c5f38$0$256$ed9e5944@.reading.news.pipex.ne t...
> Hi
> As this is not production code then you may want to check out the
> undocumented sp_MSforeachtable
>
http://groups.google.co.uk/groups?h...2%40tkmsftngp03
>
http://groups.google.co.uk/groups?h...man%40127.0.0.1
> John
> "Paul" <psampson@.uecomm.com.au> wrote in message
> news:1061944796.500758@.proxy.uecomm.net.au...
> > Hi, I'm trying to add a modified datetime and userid to all 72 tables in
> my
> > SQL 2000 database. I have the script to do one table, and a cursor, but
it
> > won't run across all tables. Any help would be appreciated. Thanks...
> > DECLARE @.tName varchar(40)
> > DECLARE C1 CURSOR FOR
> > select name from sysobjects where type = 'U'
> > OPEN C1
> > FETCH NEXT FROM C1 INTO @.tName
> > -- Check @.@.FETCH_STATUS to see if there are any more rows to fetch
> > WHILE @.@.FETCH_STATUS = 0
> > BEGIN
> > -- This is executed as long as the previous fetch succeeds
> > BEGIN TRANSACTION
> > SET QUOTED_IDENTIFIER ON
> > SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
> > SET ARITHABORT ON
> > SET NUMERIC_ROUNDABORT OFF
> > SET CONCAT_NULL_YIELDS_NULL ON
> > SET ANSI_NULLS ON
> > SET ANSI_PADDING ON
> > SET ANSI_WARNINGS ON
> > COMMIT
> > BEGIN TRANSACTION
> > ALTER TABLE @.tName ADD
> > ModifiedDT datetime NULL,
> > ModifiedUserID int NULL
> > GO
> > COMMIT
> > FETCH NEXT FROM C1
> > END
> > CLOSE C1
> > DEALLOCATE C1
> > GO

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