explain.depesz.com – new change and some stats

Quite a long time ago (in October), Oskar Liljeblad reported a bug in anonymization. Namely – group keys were not anonymized.

You can see example of such plan here.

I finally got to it, fixed the bug, pushed new version to live site, and now such plans will be correctly anonymized.

Thanks Oskar, and sorry for long delay.

Continue reading explain.depesz.com – new change and some stats

explain.depesz.com changes and new stats

Some time ago I was contacted by Adam Smith – he pointed out that subquery names in “Subquery Scan" nodes were not properly anonymized.

Now, they are, which you can see in here:

While working on it, I also added (helpful?) links from node types to my blogposts about reading explain output – Explaining the unexplainable.

Continue reading explain.depesz.com changes and new stats

New functionality on explain.depesz.com, and some statistics

Some time ago Karl Bartel asked me to add ability to parse plans that were done using “ANALYZE ON, TIMING OFF". Initially I didn't see the point, but he said that explain.depesz.com allows him to hide parts of the tree, and other columns (aside from actual time) are extracted and presented in more readable way.

OK. Got his point, but was busy. Finally today committed:

Now – plans made using analyze without timing work nicely. In process also fixed display of nodes that never were executed.

And now time for some bragging, a.k.a. statistics:

Continue reading New functionality on explain.depesz.com, and some statistics

Changes in explain.depesz.com

This time the changes do not modify how the website works. But they make it simpler to deploy clone of explain.depesz.com on your own server.

Thanks to Petr A. Korobeinikov I got full automation for setting test/development/internal clones of the site. What was done previously manually, now can be done very fast using Vagrant or Puppet.

Great stuff, thanks Petr.
Continue reading Changes in explain.depesz.com

How to install your own copy of explain.depesz.com

There are some cases where you might want to get your own copy of explain.depesz.com. You might not trust me with your explains. You might want to use it without internet access. Or you just want to play with it, and have total control over the site.

Installing, while obvious to me, and recently described by John Poole, is not always 100% clear. So, I decided to write about how to set it up, from scratch.

Continue reading How to install your own copy of explain.depesz.com

Changes on explain.depesz.com

Uploaded new version to the server – straight from GitHub. There are two changes – one visible, and one not really.

The invisible change, first, is one for people hosting explain.depesz.com on their own. As you perhaps know you can get sources of explain.depesz.com and install it on any box you want (as log as you can get there PostgreSQL, Perl, and some perl modules). While working on it on my own, I figured I could use a way to tell which version of module-xxx the site is running right now. So I build /info page (which is inaccessible to everyone, but manually-marked admins), which lists versions and interesting paths.

The second change – the one visible to users, is that I made explain.depesz.com commify numbers. Sometimes it can be hard to read value like 12325563, but now it will be displayed as 12,325,563 making is simpler to grasp.

This second change was suggested by Jacek Wielemborek, so if you hate it – blame him. Of course if you love the change – it's all on me 🙂

Hope you'll find it helpful.

Anonymize CTE names on explain.depesz.com

A colleague recently let me know that anonymization in explain.depesz.com doesn't handle CTE names. For example, in plan:

                                            QUERY PLAN                                             
---------------------------------------------------------------------------------------------------
 CTE Scan on some_name  (cost=0.01..0.03 rows=1 width=8) (actual time=0.027..0.028 rows=1 loops=1)
   CTE some_name
     ->  Result  (cost=0.00..0.01 rows=1 width=0) (actual time=0.023..0.023 rows=1 loops=1)
 Planning time: 0.217 ms
 Execution time: 0.124 ms
(5 rows)

“some_name" was kept even if anonymization was turned on.

Now it's fixed, and new code should properly anonymize all CTE names. Of course the change is live on explain.depesz.com too.

Adding plans to explain.depesz.com from your psql

So, lately I have been thinking about integrating explain.depesz.com with psql. Currently, you have to run explain, copy the output, switch to webbrowser, go to explain.depesz.coma> site, paste output, click submit. It's not that it's a lot of work, but it can be simplified.

Continue reading Adding plans to explain.depesz.com from your psql