BUG: Qualifying Table Name in Query Results in More I/O Op.

ID: Q96196

The information in this article applies to:

Microsoft SQL Server for OS/2, version 4.2
Microsoft SQL Server version 4.2x


BUG# OS/2: 1586 (4.2)
       NT:   97 (4.2)

SYMPTOMS

Fully qualifying a table name with a database name in a query results in more I/O operations and more query processing time than using a non-fully qualified table name.

Examples

Query 1 (table name not fully qualified):


   update titles
   set titles.royalty = titles.royalty
   from titles


   Result Logical reads: 92

Query 2 (table name fully qualified):


   update pubs..titles
   set titles.royalty = titles.royalty
   from titles


   Results Logical reads: 398

WORKAROUND

Use the table name without fully qualifying it with the database name. Alternatively, use fully qualified tablenames consistently throughout the query.

Example


   update pubs..titles
   set pubs..titles.royalty = pubs..titles.royalty
   from pubs..titles

STATUS

Microsoft has confirmed this to be a problem in SQL Server versions 4.2 and 4.2a for OS/2 and Microsoft SQL Server versions 4.21 and 4.21a. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

Keywords : kbother kbbug4.20 kbbug4.20a kbbug4.21 SSrvServer SSrvWinNT
Version : 4.2 4.2a | 4.21 4.21a
Platform : OS/2 WINDOWS
Issue type :