Re: range test for hash index?

On Wed, Sep 25, 2019 at 09:07:13AM +0530, Amit Kapila wrote:
>On Wed, Sep 18, 2019 at 9:30 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>>
>> On Mon, Sep 16, 2019 at 11:24 PM Paul A Jungwirth
>> <pj@illuminatedcomputing.com> wrote:
>> >
>> > On Mon, Sep 16, 2019 at 5:28 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>> > > I don't see this function on the master branch.  Is this function name
>> > > correct?  Are you looking at some different branch?
>> >
>> > Sorry about that! You're right, I was on my multirange branch. But I
>> > see the same thing on latest master (but calling hash_range instead of
>> > hash_range_internal).
>> >
>>
>> No problem, attached is a patch with a proposed commit message.  I
>> will wait for a few days to see if Heikki/Jeff or anyone else responds
>> back, otherwise will commit and backpatch this early next week.
>>
>
>Today, while I was trying to backpatch, I realized that hash indexes
>were not WAL-logged before 10 and they give warning "WARNING:  hash
>indexes are not WAL-logged and their use is discouraged".  However,
>this test has nothing to do with the durability of hash-indexes, so I
>think we can safely backpatch, but still, I thought it is better to
>check if anybody thinks that is not a good idea.   In back-branches,
>we are already using hash-index in regression tests in some cases like
>enum.sql, macaddr.sql, etc., so adding for one more genuine case
>should be fine.  OTOH, we can back-patch till 10, but the drawback is
>the tests will be inconsistent across branches.  Does anyone think it
>is not a good idea to backpatch this till 9.4?
>

By "inconsistent" you mean that pre-10 versions will have different
expected output than versions with WAL-logged hash indexes? I don't see
why that would be a reason not to backpatch to all supported versions,
considering we already have the same difference for other test suites.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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