Re: Streaming Replication and Hash Indices

On Mon, Jan 18, 2016 at 01:15:28PM +0100, Seb Mel wrote:
> Hi list,
>
> today i got bitten by the issue that streaming replication does not replicate "hash" indices as those changes are not written to WAL. That fact is documented here:
> http://www.postgresql.org/docs/current/static/indexes-types.html
>
> But i could not find that information anywhere else like:
> https://wiki.postgresql.org/wiki/Streaming_Replication#Restrictions
> or
> http://www.postgresql.org/docs/current/static/warm-standby.html
>
> I suppose it would be very helpful to add it there, as the usual policy for "corrupt slave data" is to recreate the slave from a base_backup which would make you into thinking that the issue was fixed.
> That is wrong though, as it will reappear after some time when the data in the table and the index diverge :)!

We issue a warning on hash index creation in 9.5:

Issue a warning during the creation of <link
linkend="indexes-types">hash</> indexes because they are not
crash-safe (Bruce Momjian)

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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