Indeed, hypothetical indexes are good to check potentially good
configurations without harming the whole system with actual index
creation. Please observer that we've added an "explain hypothetical"
command, that will include plans considering hypothetical indexes! We'll
try to add a simple case study that would help those wondering about
this project.
Sergio
On 3/12/2010 08:06, Richard Huxton wrote:
> On 03/12/10 08:14, Jeroen Vermeulen wrote:
>> On 2010-12-02 00:48, Ana Carolina Brito de Almeida wrote:
>>
>>> We would like to inform you all that our extension to PostgreSQL, that
>>> includes hypothetical indexes (and soon index self-tuning), is
>>> available through a sourgeforge project.
>
>> Looking at the sourceforge page, I'm left with one burning question:
>> what are they for?
>
> I believe they're for performance testing. Add hypothetical index
> (takes very little time). Check estimated costs with EXPLAIN. If good,
> add real index (takes lots of time).
>
> Of course, they're also good for indexing hypothetical data ;-)
>