Question

If I know the database-name and table-name, how can I find columns-count of the table from sql server master database?

What is the fastest way to find the columns count of any database-table?

What do you think about the performance of this query?

select count(*) from SYSCOLUMNS where id=(select id from SYSOBJECTS where name='Categories')

I need to support sql server 2000 and onwards.

Answer 1

It may vary slightly depending on the version of SQL Server, but this will work for 2005:

SELECT
     COUNT(*)
FROM
     <database name>.sys.columns
WHERE
     object_id = OBJECT_ID('<database name>.<owner>.<table name>')

In 2000:

SELECT
     COUNT(*)
FROM
     <database name>.sysobjects o
INNER JOIN <database name>.syscolumns c ON
     c.id = o.id
WHERE
     o.name = '<table name>'

If you might have multiple tables with the same exact table name under different owners then you’ll need to account for that. I forget the column name in sysobjects to look at off the top of my head.

UPDATE FOR NEWER VERSIONS OF SQL Server and ANSI compliance:

SELECT COUNT(*)
FROM
    <database name>.INFORMATION_SCHEMA.COLUMNS
WHERE
    TABLE_SCHEMA = '<table schema>' AND
    TABLE_NAME = '<table name>'