Determine if field exists - SQL Server Forums

Please start any new threads on our new site at https://forums.sqlteam.com. We've got lots of great SQL Server experts to answer whatever question you can come up with.

All Forums

SQL Server 2000 Forums

Transact-SQL (2000)

Determine if field exists

Author

Topic

anderskd
Starting Member

25 Posts

Posted - 2007-02-09 : 13:41:14

Hello,
I'm a little stumped on a solution for this problem. I am querying essentially the same tables from different databases. There is one field that I need to pull, that only exists on some of the databases. Can anyone think of an if statement or error handler that can determine which query to run based on if the field exists or not.
This is going to be ran through about 50 databases, so I need the SP to decide which statement to run.

Example

--if field ZIP exists in the table
SELECT NAME, ZIP FROM CUSTOMER
--if not exists
SELECT NAME, 'NA' FROM CUSTOMER
--END IF

Thanks for any help that may be provided!

X002548
Not Just a Number

15586 Posts

Posted - 2007-02-09 : 13:58:36

You are probably going to need to use dynamic sql and reference INFORMATION_SCHEMA.Columns

Brett

8-)

Hint: Want your questions answered fast? Follow the direction in this link
http://weblogs.sqlteam.com/brettk/archive/2005/05/25/5276.aspx

Add yourself!
http://www.frappr.com/sqlteam

anderskd
Starting Member

25 Posts

Posted - 2007-02-09 : 14:13:05

Thanks for pointing me in the right direction on this. For some reason I've never referecned the INFORMATION_SCHEMA. It is super helpful.

Here's what the code will look like:

DECLARE @PAYEXIST INT
SELECT @PAYEXIST = COUNT(*) FROM MYDATABASE.INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME = 'PAYINVOICEID'
PRINT @PAYEXIST

IF @PAYEXIST > 0
SELECT 'ITS THERE' FROM INVC_COUNT
ELSE
SELECT 'NOT THERE' FROM INVC_COUNT

Michael Valentine Jones
Yak DBA Kernel (pronounced Colonel)

7020 Posts

Posted - 2007-02-09 : 14:22:14

quote:
Originally posted by anderskd

Thanks for pointing me in the right direction on this. For some reason I've never referecned the INFORMATION_SCHEMA. It is super helpful.

Here's what the code will look like:

DECLARE @PAYEXIST INT
SELECT @PAYEXIST = COUNT(*) FROM MYDATABASE.INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME = 'PAYINVOICEID'
PRINT @PAYEXIST

IF @PAYEXIST > 0
SELECT 'ITS THERE' FROM INVC_COUNT
ELSE
SELECT 'NOT THERE' FROM INVC_COUNT

You should modify that code to make sure it is in the table you are interested in. You need to check the TABLE_SCHEMA and the TABLE_NAME in your query.

CODO ERGO SUM

anderskd
Starting Member

25 Posts

Posted - 2007-02-09 : 14:51:58

Good call Michael. I almost forgot to add that in!

Thanks

Michael Valentine Jones
Yak DBA Kernel (pronounced Colonel)

7020 Posts

Posted - 2007-02-09 : 15:01:02

Another way to do it:


if  col_length('dbo.INVC_COUNT','PAYINVOICEID') > 0
	begin
	SELECT 'ITS THERE' FROM INVC_COUNT
	end
ELSE
	begin
	SELECT 'NOT THERE' FROM INVC_COUNT
	end

CODO ERGO SUM

anderskd
Starting Member

25 Posts

Posted - 2007-02-09 : 17:16:31

New dilima on this -

Does anyone know a way to reference the INFORMATION_SCHEMA view across a linked server?

I can reference different databases on the same server like this:
SELECT @PAYEXIST = COUNT(*) FROM DB1.INFORMATION_SCHEMA.COLUMNS
SELECT @PAYEXIST = COUNT(*) FROM DB2.INFORMATION_SCHEMA.COLUMNS

--but this doesn't work
SELECT @PAYEXIST = COUNT(*) FROM SQLSERV1.DB1.INFORMATION_SCHEMA.COLUMNS

SELECT @PAYEXIST = COUNT(*) FROM SQLSERV2.DB3.INFORMATION_SCHEMA.COLUMNS

Maybe I just have the wrong syntax. I'm stumped.

Michael Valentine Jones
Yak DBA Kernel (pronounced Colonel)

7020 Posts

Posted - 2007-02-09 : 18:30:59

Try this:


select count(*)
from openquery(SQLSERV1,'Select * from DB1.INFORMATION_SCHEMA.COLUMNS)

CODO ERGO SUM

anderskd
Starting Member

25 Posts

Posted - 2007-02-09 : 18:49:07

The problem is that I wanted to pass the database and SS name in as variables. The Servername I can handle by a CASE statement (becuase there are only two of them). But when I dynamically put together the select statement together as a string and pass that into the openquery I get errors.

It's allright if this doesn't get resolved. I ended up just making two stored procedures. One for DBs that have the field and one for the ones that don't From there it's pretty easy to create exec statements from select statements to decide which of the SPs to run.

Thanks for all the help Michael. I've learned a lot from your assistance today!

Kelly

Subscribe to SQLTeam.com

SQLTeam.com Articles via RSS

SQLTeam.com Weblog via RSS

- Advertisement -

Resources