SyntaxDBCC PINTABLE ( database_id , table_id )
This was discontinued from sql server 2005 but can use in 2000.
Here is some info I got from MSDN:
DBCC PINTABLE does not cause the table to be read into memory. As the pages from the table are read into the buffer cache by normal Transact-SQL statements, they are marked as pinned pages. SQL Server does not flush pinned pages when it needs space to read in a new page. SQL Server still logs updates to the page and, if necessary, writes the updated page back to disk. SQL Server does, however, keep a copy of the page available in the buffer cache until the table is unpinned with the DBCC UNPINTABLE statement.
DBCC PINTABLE is best used to keep small, frequently referenced tables in memory. The pages for the small table are read into memory one time, then all future references to their data do not require a disk read