Subtransaction documentation

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Attached is a diff for subtransactions. I modified the SQL reference
section and touched on the various commands therein. I didn't mention
anything about cursors or portals, because I bet they will be resolved
before long.

I looked at the tutorial pages and the MVCC pages and I decided that
subtransactions don't really belong in either place. People who want them
will know they need them when they encounter a situation that demands
them. I see them being used mostly in PL/pgSQL type situations.

Maybe some documentation on the internals is warranted - but I don't know
nearly enough on that to do that task.

- --
Jonathan Gardner
jgardner@jonathangardner.net
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (GNU/Linux)

iD8DBQFA+Xngqp6r/MVGlwwRAot7AJ9DBZSk1l0vkSDsaQzYUWe16jKh4wCeJ+AM
njA7/4j/mawBwOLKw8GykxY=
=415C
-----END PGP SIGNATURE-----