Re: = TRUE vs IS TRUE confuses partition index creation

On Wed, Aug 17, 2022 at 5:57 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:

> IIRC, "b = true" will be simplified to just "b" somewhere in expression
> preprocessing.  I'm betting that something in the partitioned index
> matching code is applying that preprocessing to one index predicate and
> not the other, whereupon they look different.  If that's the explanation,
> there are likely other cases that should match and fail to.


Yeah, you're right. The matching work happens in indexcmds.c, using
CompareIndexInfo to compare 'cldIdxInfo' and 'indexInfo'. The
'cldIdxInfo' is constructed with BuildIndexInfo, which would run index
expressions and index predicates through const-simplification before
creating the IndexInfo node. While 'indexInfo' is created without any
const-simplification.

This can be verified with the attached changes, which would make it work
for this case.

Thanks
Richard