Waiting for 9.1 – Faster LIKE/ILIKE

On 1st of February, Tom Lane committed patch:

Support LIKE and ILIKE index searches via contrib/pg_trgm indexes.
 
Unlike Btree-based LIKE optimization, this works for non-left-anchored
search patterns.  The effectiveness of the search depends on how many
trigrams can be extracted from the pattern.  (The worst case, with no      
trigrams, degrades to a full-table scan, so this isn't a panacea.  But   
it can be very useful.)                                                 
 
Alexander Korotkov, reviewed by Jan Urbanski

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Waiting for 9.1 – Add UNIQUE/PRIMARY KEY with index

On 25th of January, Tom Lane committed patch:

Implement ALTER TABLE ADD UNIQUE/PRIMARY KEY USING INDEX.
 
This feature allows a unique or pkey constraint to be created using an
already-existing unique index.  While the constraint isn't very
functionally different from the bare index, it's nice to be able to do that
for documentation purposes.  The main advantage over just issuing a plain
ALTER TABLE ADD UNIQUE/PRIMARY KEY is that the index can be created with
CREATE INDEX CONCURRENTLY, so that there is not a long interval where the
table is locked against updates.
 
On the way, refactor some of the code in DefineIndex() and index_create()
so that we don't have to pass through those functions in order to create
the index constraint's catalog entries.  Also, in parse_utilcmd.c, pass
around the ParseState pointer in struct CreateStmtContext to save on
notation, and add error location pointers to some error reports that didn't
have one before.
 
Gurjeet Singh, reviewed by Steve Singer and Tom Lane

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Waiting for 9.1 – sepgsql

On 24th of January, Robert Haas committed very important patch:

sepgsql, an SE-Linux integration for PostgreSQL
 
This is still pretty rough - among other things, the documentation
needs work, and the messages need a visit from the style police -
but this gets the basic framework in place.
 
KaiGai Kohei

Now, In this place I usually show you what it is all about, but it's not going to happen with this patch. Reason is very simple – I know that it's important, and that it integrates PostgreSQL with SE/Linux, but since I never played with SE/Linux – I cannot really show you anything in here.

But – if you know anything about SE/Linux and sepgsql, I would like to ask you to describe this extension so that even I could understand it.

Sorry – I know I should put more in here, but it simply is so far above my knowledge limits, it would take me too long time to get through documentation for SE/Linux and sepgsql.

For now – if you want to know more – simply check the docs.

Waiting for 9.1 – pg_basebackup

On 23rd of January, Magnus Hagander committed patch which adds:

Add pg_basebackup tool for streaming base backups
 
This tool makes it possible to do the pg_start_backup/
copy files/pg_stop_backup step in a single command.
 
There are still some steps to be done before this is a
complete backup solution, such as the ability to stream
the required WAL logs, but it's still usable, and
could do with some buildfarm coverage.
 
In passing, make the checkpoint request optionally
fast instead of hardcoding it.
 
Magnus Hagander, reviewed by Fujii Masao and Dimitri Fontaine

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Waiting for 9.1 – Unlogged tables

On 29th of December, Robert Haas committed interesting patch, which does:

Support unlogged tables.
 
The contents of an unlogged table aren't WAL-logged; thus, they are not
available on standby servers and are truncated whenever the database
system enters recovery.  Indexes on unlogged tables are also unlogged.
Unlogged GiST indexes are not currently supported.

(edited commit message, due to this mail.

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Waiting for 9.1 – KNNGIST

On 4th of December, Tom Lane committed really cool patch:

KNNGIST, otherwise known as order-by-operator support for GIST.

This commit represents a rather heavily editorialized version of
Teodor's builtin_knngist_itself-0.8.2 and builtin_knngist_proc-0.8.1
patches.  I redid the opclass API to add a separate Distance method
instead of turning the Consistent method into an illogical mess,
fixed some bit-rot in the rbtree interfaces, and generally worked over
the code style and comments.
 
There's still no non-code documentation to speak of, but I'll work on
that separately.  Some contrib-module changes are also yet to come
(right now, point <-> point is the only KNN-ified operator).
 
Teodor Sigaev and Tom Lane

Continue reading Waiting for 9.1 – KNNGIST

Waiting for 9.1 – format()

On 21st of November Robert Haas committed new patch, which adds new function:

Add new SQL function, format(text).

Currently, three conversion format specifiers are supported: %s for a
string, %L for an SQL literal, and %I for an SQL identifier.  The latter
two are deliberately designed not to overlap with what sprintf() already
supports, in case we want to add more of sprintf()'s functionality here
later.
 
Patch by Pavel Stehule, heavily revised by me.  Reviewed by Jeff Janes
and, in earlier versions, by Itagaki Takahiro and Tom Lane.

Continue reading Waiting for 9.1 – format()

Waiting for 9.1 – Removed autocast footgun

On 8th of November, Tom Lane committed patch, which doesn't provide any new features, but removes one of the more annoying footguns in PostgreSQL:

Prevent invoking I/O conversion casts via functional/attribute notation.
 
PG 8.4 added a built-in feature for casting pretty much any data type to
string types (text, varchar, etc).  We allowed this to work in any of the
historically-allowed syntaxes: CAST(x AS text), x::text, text(x), or
x.text.  However, multiple complaints have shown that it's too easy to
invoke such casts unintentionally in the latter two styles, particularly
field selection.  To cure the problem with the narrowest possible change
of behavior, disallow use of I/O conversion casts from composite types to
string types via functional/attribute syntax.  The new functionality is
still available via cast syntax.
 
In passing, document the equivalence of functional and attribute syntax
in a more visible place.

Continue reading Waiting for 9.1 – Removed autocast footgun