On 17th of July, Noah Misch committed patch:
Implement the FILTER clause for aggregate function calls. This is SQL-standard with a few extensions, namely support for subqueries and outer references in clause expressions. catversion bump due to change in Aggref and WindowFunc. David Fetter, reviewed by Dean Rasheed.
Continue reading Waiting for 9.4 – Implement the FILTER clause for aggregate function calls.
On 16th of July, Kevin Grittner committed patch:
Add support for REFRESH MATERIALIZED VIEW CONCURRENTLY. This allows reads to continue without any blocking while a REFRESH runs. The new data appears atomically as part of transaction commit. Review questioned the Assert that a matview was not a system relation. This will be addressed separately. Reviewed by Hitoshi Harada, Robert Haas, Andres Freund. Merged after review with security patch f3ab5d4.
Continue reading Waiting for 9.4 – Add support for REFRESH MATERIALIZED VIEW CONCURRENTLY.
On 28th of June, Simon Riggs committed patch:
ALTER TABLE ... ALTER CONSTRAINT for FKs Allow constraint attributes to be altered, so the default setting of NOT DEFERRABLE can be altered to DEFERRABLE and back. Review by Abhijit Menon-Sen
Continue reading Waiting for 9.4 – ALTER TABLE … ALTER CONSTRAINT for FKs
Looong time ago, I wrote a piece about removing bloat by moving rows away from the end of table, and vacuuming it.
This is/was very slow, and was optimized (to some extent) by Nathan Thom, but his blogpost vanished. Besides, later on we got great tool: pg_reorg (or, as it's currently named: pg_repack).
But recently I was in position where I couldn't pg_reorg. So I had to look for other way. And I found it 🙂
In previous posts in this series, I talked about how to read EXPLAIN output, and what each line (operation/node) means.
Now, in the final post, I will try to explain how it happens that Pg chooses “Operation X" over “Operation Y".
In this, hopefully 2nd to last, post in the series, I will cover the rest of usually happening operations that you can see in your explain outputs.
Word of warning: this blogpost is about thing related to Bash (well, maybe other shells too, didn't really test), but since I found it while doing Pg work, and it might bite someone else doing Pg related work, I decided to add it to “postgresql" tag.
So, due to some work I had to do, I needed a quick, repeatable way to setup some Pg instances, replication between them, and some data loader. All very simple, no real problems. At least that's what I thought…
In previous post in the series I wrote about how to interpret single line in explain analyze output, it's structure, and later on described all basic data-getting operations (nodes in explain tree).
Today, we'll move towards more complicated operations.
Last time I wrote about what explain output shows. Now I'd like to talk more about various types of “nodes" / operations that you might see in explain plans.
Around the time that Xzilla wrote about the book, Packt contacted me and asked for a review.
Since I generally don't really read technical books, I declined the offer, but Sandy from Packt was very persistent, and asked if I could inform about book giveaway contest.
The book is definitely PostgreSQL related, and Xzilla suggested to check it out, so here it goes:
Continue reading Win a book contest – PostgreSQL Backup and Restore How-to