Fix ANALYZE crash with custom types

[nikkhils]

Extensions like PostGIS introduce custom datatypes for columns. They
also have custom statistics for such custom types. We already state in
our comments that stats for custom types are not supported but it was
never tested. Fix that now.

Fixes #3733

[codecov]

Codecov Report

Merging #3745 (e4a174e) into master (0fecefd) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #3745      +/-   ##
==========================================
- Coverage   90.29%   90.29%   -0.01%     
==========================================
  Files         213      213              
  Lines       37655    37654       -1     
==========================================
- Hits        34001    33999       -2     
- Misses       3654     3655       +1     

Impacted Files	Coverage Δ
tsl/src/chunk_api.c	94.88% <100.00%> (ø)
tsl/src/nodes/data_node_dispatch.c	97.10% <0.00%> (-0.25%)	⬇️
tsl/src/bgw_policy/job.c	87.50% <0.00%> (-0.06%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 0fecefd...e4a174e. Read the comment docs.

[svenklemm]

Please add changelog entry

[erimatnor]

Is it possible to add a test by creating a custom type (CREATE TYPE) and then use it in a distributed hypertable that we ANALYZE?

[nikkhils]

Is it possible to add a test by creating a custom type (CREATE TYPE) and then use it in a distributed hypertable that we ANALYZE?

No. For this to happen, we need a custom STATISTIC type, not just custom type and that can happen only via PostGIS or other external components.

[nikkhils]

Please add changelog entry

Done. Thanks

[pmwkaa]

Is it possible to add a test by creating a custom type (CREATE TYPE) and then use it in a distributed hypertable that we ANALYZE?

No. For this to happen, we need a custom STATISTIC type, not just custom type and that can happen only via PostGIS or other external components.

I guess we could introduce such a type in the C part of testing, unless it is unnecessary complicated

[erimatnor]

Is it possible to add a test by creating a custom type (CREATE TYPE) and then use it in a distributed hypertable that we ANALYZE?

No. For this to happen, we need a custom STATISTIC type, not just custom type and that can happen only via PostGIS or other external components.

Isn't it possible to just alias an existing type and reference its stats function? Similar to this:

timescaledb/test/sql/custom_type.sql

Line 7 in 0fecefd

CREATE OR REPLACE FUNCTION customtype_in(cstring) RETURNS customtype AS

[nikkhils]

Is it possible to add a test by creating a custom type (CREATE TYPE) and then use it in a distributed hypertable that we ANALYZE?

No. For this to happen, we need a custom STATISTIC type, not just custom type and that can happen only via PostGIS or other external components.

Isn't it possible to just alias an existing type and reference its stats function? Similar to this:

timescaledb/test/sql/custom_type.sql

Line 7 in 0fecefd

CREATE OR REPLACE FUNCTION customtype_in(cstring) RETURNS customtype AS

The only way to do this would be in C code to introduce a new stats kind entry with value more than 99 or 1000 or something. Not sure it's worth the hassle.