Waiting for 9.2 – split of current_query in pg_stat_activity

On 19t of January, Magnus Hagander committed patch:

Separate state from query string in pg_stat_activity
 
This separates the state (running/idle/idleintransaction etc) into
it's own field ("state"), and leaves the query field containing just
query text.
 
The query text will now mean "current query" when a query is running
and "last query" in other states. Accordingly,the field has been
renamed from current_query to query.
 
Since backwards compatibility was broken anyway to make that, the procpid
field has also been renamed to pid - along with the same field in
pg_stat_replication for consistency.
 
Scott Mead and Magnus Hagander, review work from Greg Smith

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Waiting for 9.2 – NULLS from pg_*_size() functions

On 19t of January, Heikki Linnakangas committed patch:

Make pg_relation_size() and friends return NULL if the object doesn't exist.
 
That avoids errors when the functions are used in queries like "SELECT
pg_relation_size(oid) FROM pg_class", and a table is dropped concurrently.
 
Phil Sorber

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Waiting for 9.2 – excluding data of table from dump

On 14h of December, Andrew Dunstan committed patch:

Add --exclude-table-data option to pg_dump.
 
Andrew Dunstan, reviewed by Josh Berkus, Robert Haas and Peter Geoghegan.
 
This allows dumping of a table definition but not its data, on a per table basis.
Table name patterns are supported just as for --exclude-table.

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Waiting for 9.2 – Index only scans

On 8th of October, Tom Lane committed patch:

Support index-only scans using the visibility map to avoid heap fetches.
 
When a btree index contains all columns required by the query, and the
visibility map shows that all tuples on a target heap page are
visible-to-all, we don't need to fetch that heap page.  This patch depends
on the previous patches that made the visibility map reliable.
 
There's a fair amount left to do here, notably trying to figure out a less
chintzy way of estimating the cost of an index-only scan, but the core
functionality seems ready to commit.
 
Robert Haas and Ibrar Ahmed, with some previous work by Heikki Linnakangas.

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Waiting for 9.2 – filtered info in explain analyze

On 22nd of September, Tom Lane committed patch:

Make EXPLAIN ANALYZE report the numbers of rows rejected by filter steps.
 
This provides information about the numbers of tuples that were visited
but not returned by table scans, as well as the numbers of join tuples
that were considered and discarded within a join plan node.
 
There is still some discussion going on about the best way to report counts
for outer-join situations, but I think most of what's in the patch would
not change if we revise that, so I'm going to go ahead and commit it as-is.
 
Documentation changes to follow (they weren't in the submitted patch
either).
 
Marko Tiikkaja, reviewed by Marc Cousin, somewhat revised by Tom

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Waiting for 9.2 – cascading streaming replication

On 19th of July, Simon Riggs committed patch:

Cascading replication feature FOR streaming log-based replication.
Standby servers can now have WALSender processes, which can WORK WITH
either WALReceiver OR archive_commands TO pass DATA. Fully updated
docs, including NEW conceptual terms OF sending server, upstream AND
downstream servers. WALSenders TERMINATED WHEN promote TO master.
 
Fujii Masao, review, rework AND doc rewrite BY Simon Riggs

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Waiting for 9.2 – Stacked Diagnostics in PL/pgSQL

On 18th of July, Tom Lane committed patch:

Add GET STACKED DIAGNOSTICS plpgsql command to retrieve exception info.
 
This is more SQL-spec-compliant, more easily extensible, and better
performing than the old method of inventing special variables.
 
Pavel Stehule, reviewed by Shigeru Hanada and David Wheeler

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