* ALTER ... ADD COLUMN with defaults and NOT NULL constraints works per SQL
spec.  A default is implemented by rewriting the table with the new value
stored in each row.

* ALTER COLUMN TYPE.  You can change a column's datatype to anything you
want, so long as you can specify how to convert the old value.  Rewrites
the table.  (Possible future improvement: optimize no-op conversions such
as varchar(N) to varchar(N+1).)

* Multiple ALTER actions in a single ALTER TABLE command.  You can perform
any number of column additions, type changes, and constraint additions with
only one pass over the table contents.

Basic documentation provided in ALTER TABLE ref page, but some more docs
work is needed.

Original patch from Rod Taylor, additional work from Tom Lane.

> Please find a attached a small patch that adds accessor functions
> for "aclitem" so that it is not an opaque datatype.
>
> I needed these functions to browse aclitems from user land. I can load
> them when necessary, but it seems to me that these accessors for a
> backend type belong to the backend, so I submit them.
>
> Fabien Coelho

< 	o Add ALTER TABLE table SET WITHOUT CLUSTER
> 	o Add ALTER TABLE table SET WITHOUT CLUSTER (Christopher)

        o Add ALTER TABLE table SET WITHOUT CLUSTER

Andrew Dunstan

 * correct platform specific regression files are used under ming
 * pwd prints out a usable win32 pathname

Claudio Natoli

Jun Kuwamura

Move timezone database to share/timezone.

#ifndef HAVE_SYMLINK
#define HAVE_SYMLINK 0
#endif

system headers.

Allow system to find timezone database by pasing pkglibdir into the
binary via a define.

Timezone code backend integration done by Magnus Hagander.

from our code.

<   columns and indexes with many duplicate keys