Hey. I'm creating an extention in C. An extention will be fired as, or
inside, a trigger.
What I need: dynamically, inside a trigger, identify which column, or
columns if the primary key is composed of multiple columns, form the
primary key -- their indexes or names.
I need a fast way, therefore I don't consider using SPI_exec(..) and the
like.
I was suggested to use `get_primary_key_attnos` from
`src/include/catalog/pg_constraint.h`
extern Bitmapset *get_primary_key_attnos(Oid relid, bool deferrableOk)
It returns *Bitstamp. And it's got "nwords" and "words[]". But those
return just big numbers, not something that look similar to an index of
the primary key column.
And therefore I haven't had any luck thus far.
How to do it?