Archives of the TeradataForum
Message Posted: Wed, 18 Dec 2003 @ 01:23:36 GMT
| Subj: || || Re: Collect Stats on Single Column SI |
| From: || || Christie, Jon |
No, exactly the same thing. Well... Almost.
You pose an interesting question. When you drop a secondary index, the rows in DBC.Indexes defining that index will be deleted from the
table. The statistics are stored in those rows, so they'll go too. If it was a single-column index, the stats would be stored in
DBC.TVFields. I've never checked to see if they're removed or not. I'd assume that they are. Guess I'd have to take a look at an
If you collect stats on multiple columns using the columns syntax, we put dummy rows in DBC.Indexes as though there were a secondary
index, but we never build a secondary index subtable. Now if you happen to have a secondary index on the same columns, the stats should not
go away if you drop the index. That's why I said almost.