Re: pg_class catalog question...

[Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>]

"Jonah H. Harris" <jonah(dot)harris(at)gmail(dot)com> writes:
> Does anyone know how to add a fixed-length char field to pg_class?

Changing any of the bootstrap catalogs is fairly tricky --- there are a
lot of places you have to update manually.  I'd suggest looking for a
previous commit that did something similar and studying the diff.
[ digs in CVS log... ]  Here are a couple of possibilities; the first
one is smaller but it's touching pg_proc not pg_class.

2005-03-29 14:44  tgl

	* doc/src/sgml/bki.sgml, doc/src/sgml/catalogs.sgml,
	src/backend/bootstrap/bootstrap.c, src/backend/catalog/pg_proc.c,
	src/include/catalog/catversion.h,
	src/include/catalog/pg_attribute.h, src/include/catalog/pg_class.h,
	src/include/catalog/pg_proc.h: Add proallargtypes and proargmodes
	columns to pg_proc, as per my earlier proposal for OUT parameter
	support.  The columns don't actually *do* anything yet, they are
	just left NULLs.  But I thought I'd commit this part separately as
	a fairly pure example of the tasks needed when adding a column to
	pg_proc or one of the other core system tables.

2002-03-26 14:15  tgl

	* doc/src/sgml/catalogs.sgml, src/backend/access/heap/heapam.c,
	src/backend/access/index/indexam.c,
	src/backend/bootstrap/bootparse.y,
	src/backend/bootstrap/bootstrap.c, src/backend/catalog/Makefile,
	src/backend/catalog/aclchk.c, src/backend/catalog/genbki.sh,
	src/backend/catalog/heap.c, src/backend/catalog/index.c,
	src/backend/catalog/indexing.c, src/backend/catalog/namespace.c,
	src/backend/commands/cluster.c, src/backend/commands/command.c,
	src/backend/commands/comment.c, src/backend/commands/creatinh.c,
	src/backend/commands/indexcmds.c, src/backend/commands/rename.c,
	src/backend/commands/trigger.c, src/backend/commands/user.c,
	src/backend/executor/execMain.c, src/backend/parser/analyze.c,
	src/backend/parser/parse_clause.c,
	src/backend/parser/parse_relation.c,
	src/backend/rewrite/rewriteDefine.c, src/backend/tcop/utility.c,
	src/backend/utils/adt/acl.c, src/backend/utils/cache/catcache.c,
	src/backend/utils/cache/lsyscache.c,
	src/backend/utils/cache/relcache.c,
	src/backend/utils/cache/syscache.c, src/include/access/genam.h,
	src/include/access/heapam.h, src/include/bootstrap/bootstrap.h,
	src/include/catalog/catversion.h, src/include/catalog/heap.h,
	src/include/catalog/index.h, src/include/catalog/indexing.h,
	src/include/catalog/namespace.h,
	src/include/catalog/pg_attribute.h, src/include/catalog/pg_class.h,
	src/include/commands/cluster.h, src/include/commands/command.h,
	src/include/commands/comment.h, src/include/commands/defrem.h,
	src/include/commands/rename.h, src/include/nodes/parsenodes.h,
	src/include/nodes/primnodes.h, src/include/utils/catcache.h,
	src/include/utils/lsyscache.h, src/include/utils/rel.h,
	src/include/utils/relcache.h, src/include/utils/syscache.h,
	src/pl/plpgsql/src/pl_comp.c: pg_class has a relnamespace column. 
	You can create and access tables in schemas other than the system
	namespace; however, there's no search path yet, and not all
	operations work yet on tables outside the system namespace.

			regards, tom lane