Re: [PATCH v1] Fix propagation of indimmediate flag in index_create_copy

On 2026-Jul-20, Nitin Motiani wrote:

> It was reported in [1] that Reindex Concurrently for indexes with
> deferrable constraints doesn't honour the deferrable constraints while
> the operations is running. And the transactions can fail because the
> constraint is enforced before commit.
>
> I'm proposing a patch here which correctly copies the flag from the
> old index to the new one. Please take a look.

Hah, that was quick, thanks! This fails the isolation tests for me
though, with this backtrace:

#4 0x00005618d76672d6 in ExceptionalCondition (
conditionName=conditionName(at)entry=0x5618d77741a8 "(constr_flags == 0) || ((flags & INDEX_CREATE_ADD_CONSTRAINT) != 0)",
fileName=fileName(at)entry=0x5618d7773e58 "../../pgsql/source/master/src/backend/catalog/index.c", lineNumber=lineNumber(at)entry=773)
at ../../pgsql/source/master/src/backend/utils/error/assert.c:65
#5 0x00005618d7271fd5 in index_create (heapRelation=heapRelation(at)entry=0x7f13e9ce85d0,
indexRelationName=indexRelationName(at)entry=0x5618fe816e58 "uq_val_ccnew", indexRelationId=indexRelationId(at)entry=0,
parentIndexRelid=parentIndexRelid(at)entry=0, parentConstraintId=parentConstraintId(at)entry=0, relFileNumber=relFileNumber(at)entry=0,
indexInfo=0x5618fe816aa8, indexColNames=0x5618fe6c8d40, accessMethodId=403, tableSpaceId=0, collationIds=0x5618fe73e2f8,
opclassIds=0x7f13e9cead80, opclassOptions=0x5618fe6c8ea0, coloptions=0x7f13e9cead9c, stattargets=0x5618fe80d748, reloptions=0, flags=140,
constr_flags=2, allow_system_table_mods=true, is_internal=false, constraintId=0x0) at ../../pgsql/source/master/src/backend/catalog/index.c:773
#6 0x00005618d727248d in index_create_copy (heapRelation=heapRelation(at)entry=0x7f13e9ce85d0, flags=flags(at)entry=140, oldIndexId=33725,
tablespaceOid=0, newName=0x5618fe816e58 "uq_val_ccnew") at ../../pgsql/source/master/src/backend/catalog/index.c:1468
#7 0x00005618d72cbd46 in ReindexRelationConcurrently (stmt=stmt(at)entry=0x5618fe712228, relationOid=relationOid(at)entry=33722,
params=params(at)entry=0x7ffcf8ab62f8) at ../../pgsql/source/master/src/backend/commands/indexcmds.c:4117
#8 0x00005618d72cd892 in ReindexTable (stmt=0x5618fe712228, params=0x7ffcf8ab62f8, isTopLevel=true)
at ../../pgsql/source/master/src/backend/commands/indexcmds.c:3227
#9 ExecReindex (pstate=pstate(at)entry=0x5618fe6c8c30, stmt=stmt(at)entry=0x5618fe712228, isTopLevel=isTopLevel(at)entry=true)
at ../../pgsql/source/master/src/backend/commands/indexcmds.c:3042

This is during the
REINDEX TABLE CONCURRENTLY reind_deferred;
execution.

--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
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