Re: Simple Index question

In article <385A7F75.783EBE84_at_yahoo.com>,   boo <boo_at_yahoo.com> wrote:
> I have a relatively simple index question;
> A developer has asked that an index be placed on a table column that
> stores either a 1 or 0 value.
> There are two other indexes on this particular table.

Given that there are only two values for this column, a regular b-tree index would be of little value. You can, however, create a bitmap index on this column, which is ideal for columns of low cardinality, provided you are running at least Oracle 8x. The question of whether or not this bitmap index will actually be of any value depends upon your queries. That is, does the query access the column in the WHERE clause? I've seen excellent improvements in queries using bitmap indexes so long as the column is referenced in the where clause of the query. Also, keep in mind that creating additional indexes incurs more storage and slows down update, delete and insert statements.

> I'm not sure if this will actually help anything, but would appreciate
> any discenting viewpoints and opinions.
>
> Thanks in advance.
>
>

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Before you buy. Received on Fri Dec 17 1999 - 15:40:30 CST