Re: [HACKERS] jsonb_to_tsvector should be immutable

Josh Berkus <josh@berkus.org> writes:
> select proname, prosrc, proargtypes, provolatile from pg_proc where
> proname = 'to_tsvector';

Slightly more readable version:

regression=# select oid::regprocedure, provolatile, proparallel from pg_proc where proname = 'to_tsvector';
oid             | provolatile | proparallel  
------------------------------+-------------+-------------to_tsvector(jsonb)           | s           |
sto_tsvector(regconfig,text) | i           | sto_tsvector(text)            | s           | sto_tsvector(json)
| s           | sto_tsvector(regconfig,jsonb) | s           | sto_tsvector(regconfig,json)  | s           | s 
(6 rows)

> Both of the _byid functions should be marked immutable, no?  Otherwise
> how can users use the new functions for indexing?

Yeah, if the (regconfig,text) one is considered immutable, I don't see
why the other two aren't.  The justification for the other three being
only stable is that they depend on default_text_search_config.

(You could argue that none of these should be immutable because text
search configurations are changeable, but we already decided to ignore
that for the (regconfig,text) case.)
        regards, tom lane