Re: Invisible Indexes

On 06/18/2018 05:46 PM, Jaime Casanova wrote:
> On 18 June 2018 at 16:36, Andrew Dunstan <andrew(dot)dunstan(at)2ndquadrant(dot)com> wrote:
>> This is a MySQL feature, where an index is not considered by the planner.
>> Implementing it should be fairly straightforward, adding a new boolean to
>> pg_index, and options to CREATE INDEX and ALTER INDEX. I guess VISIBLE would
>> become a new unreserved keyword.
>>
>> The most obvious use case is to see what the planner does when the index is
>> not visible, for example which other index(es) it might use. There are
>> probably other cases where we might want an index to enforce a constraint
>> but not to be used in query planning.
>>
>> So, do we want this feature? If we do I'll go ahead and prepare a patch.
>>
> should pg_index.indisvalid works for this? in that case you only need
> the syntax for it...
>

I thought about that. But I think these are more or less orthogonal.  I
doubt it will involve lots of extra code, though.

cheers

andrew

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Andrew Dunstan https://www.2ndQuadrant.com
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