Archives of the TeradataForum
Message Posted: Thu, 06 Feb 2003 @ 19:58:08 GMT
| Subj: || || Re: Volatile vs. Global |
| From: || || Steve Wyatt |
A volatile table has a true 'temporary', no-footprint (spool only) existence, and is well-suited for session-specific, non-persistent
data needs. The global table will create an entry into the data dictionary, to allow others to use the table structure, also requiring PERM
space and system overhead. If you don't need that added benefit, then use VT's instead.
We use VT's when we need non-persistent results that are still required though the entire user session , or at least through multiple SQL
statements in a logical unit of work. They are excellent in job-stream processing - use them and throw them away - without impacting the
DD. Think of it as a derived table that can live through the whole session instead of only within the scope of a single SQL statement.