pgsql: During the split, set checksum on an empty hash index page.

During the split, set checksum on an empty hash index page.

On a split, we allocate a new splitpoint's worth of bucket pages wherein
we initialize the last page with zeros which is fine, but we forgot to set
the checksum for that last page.

We decided to back-patch this fix till 10 because we don't have an easy
way to test it in prior versions.  Another reason is that the hash-index
code is changed heavily in 10, so it is not advisable to push the fix
without testing it in prior versions.

Author: Amit Kapila
Reviewed-by: Yugo Nagata
Backpatch-through: 10
Discussion: https://postgr.es/m/5d03686d-727c-dbf8-0064-bf8b97ffe850@2ndquadrant.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3b7a96a619f78f80b4a470a0dcde4c92b5b7141f

Modified Files
--------------
src/backend/access/hash/hashpage.c | 1 +
1 file changed, 1 insertion(+)