where rownum=1 query taking time in Oracle

Question

I am trying to execute a query like

select * from tableName where rownum=1

This query is basically to fetch the column names of the table.There are more than million records in the table.When I put the above condition its taking so much time to fetch the first row.Is there any alternate to get the first row.

Answer 1

Try this:

select * from tableName where rownum<=1

There are some weird ROWNUM bugs, sometimes changing the query very slightly will fix it. I've seen this happen before, but I can't reproduce it.

Here are some discussions of similar issues: http://jonathanlewis.wordpress.com/2008/03/09/cursor_sharing/ and http://forums.oracle.com/forums/thread.jspa?threadID=946740&tstart=1