Re: Strange behaviour of function based index

g.entelmann_at_t-online.de wrote:

> Hello,
>
> I encountered some strange behaviour of a function based index.
>
> The Index: Create Index FooIndex on Footable(Trunc(aDate));
>
> Executing the following query uses the index:
>
> select Count(aDate) from Footable where Trunc(aDate) = Trunc(Sysdate);
>
> But when I use the query without the 'Count', it uses a full table scan.
>
> Can anyone explain this ??
>
>
> Gerrit

Without seeing the SQL, knowing what version, and knowing whether your used DBMS_STATS to create statistics for the CBO? No.

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Daniel Morgan
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