9f9682783b
This allows AM-specific knowledge to be applied during creation of pg_amop and pg_amproc entries. Specifically, the AM knows better than core code which entries to consider as required or optional. Giving the latter entries the appropriate sort of dependency allows them to be dropped without taking out the whole opclass or opfamily; which is something we'd like to have to correct obsolescent entries in extensions. This callback also opens the door to performing AM-specific validity checks during opclass creation, rather than hoping than an opclass developer will remember to test with "amvalidate". For the most part I've not actually added any such checks yet; that can happen in a follow-on patch. (Note that we shouldn't remove any tests from "amvalidate", as those are still needed to cross-check manually constructed entries in the initdb data. So adding tests to "amadjustmembers" will be somewhat duplicative, but it seems like a good idea anyway.) Patch by me, reviewed by Alexander Korotkov, Hamid Akhtar, and Anastasia Lubennikova. Discussion: https://postgr.es/m/4578.1565195302@sss.pgh.pa.us
The PostgreSQL contrib tree
---------------------------
This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
because they address a limited audience or are too experimental to be
part of the main source tree. This does not preclude their
usefulness.
User documentation for each module appears in the main SGML
documentation.
When building from the source distribution, these modules are not
built automatically, unless you build the "world" target. You can
also build and install them all by running "make all" and "make
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.
Some directories supply new user-defined functions, operators, or
types. To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command. In a fresh database,
you can simply do
CREATE EXTENSION module_name;
See the PostgreSQL documentation for more information about this
procedure.