I am working on AWS RDS Postgres v9.6, and also v14. I noticed that in our
shared_preload_libraries parameter, we have
pg_stat_statement included. I don't understand why that needs to be there.
In the Postgres docs, it says this:
The module must be loaded by adding pg_stat_statements to shared_preload_libraries in postgresql.conf, because it requires additional shared memory. This means that a server restart is needed to add or remove the module.
However, several other extensions are already built in - for example we use
hstore. These do not need to be in
shared_preload_libraries. Why does
pg_stat_statement behave differently?
I think shedding light on this would help me (and hopefully others) better understand how built in libraries work, especially as regards the
shared_preload_libraries parameter. The docs don't seem to say enough on this topic, or else I don't know where to find it.