William WAISSE <wwaisse(at)esprit-equipe(dot)fr> writes:
> does a documentation exists concerning postgres internals, which I
> havren't found, and which would say something like
> "the relation between pg_class and pg_attribute is the field
> oid in in pg_class which is the same as the field attrelid in pg_attribute"
> "attnum in pg_attribute is >0 for 'user' fields and <0 for internal fields"
> . . .
See the "system catalogs" chapter of the developer's guide. It's a bit
terse but I believe the information you mention above is all stated at,
eg,
http://candle.pha.pa.us/main/writings/pgsql/sgml/catalog-pg-attribute.html
regards, tom lane