Re: PoC/WIP: Extended statistics on expressions

Tomas Vondra <tomas.vondra@enterprisedb.com> writes:
> On 6/6/21 7:37 AM, Noah Misch wrote:
>> This added a "transformed" field to CreateStatsStmt, but it didn't mention
>> that field in src/backend/nodes.  Should those functions handle the field?

> Yup, that's a mistake - it should do whatever CREATE INDEX is doing. Not
> sure if it can result in error/failure or just inefficiency (due to
> transforming the expressions repeatedly), but it should do whatever
> CREATE INDEX is doing.

I'm curious about how come the buildfarm didn't notice this.  The
animals using COPY_PARSE_PLAN_TREES should have failed.  The fact
that they didn't implies that there's no test case that makes use
of a nonzero value for this field, which seems like a testing gap.

            regards, tom lane