Changes on – extracted query from auto-explain plans

Some time ago James Courtney reported missing functionality.

Specifically, when one uses auto-explain, logged explains contain query text. So, when such explain is then pasted on, it stands to reason that it should be able to extract the query on its own, without having to manually extract it and put it in query box.

It took me a while, but finally, got it working today. And you can see it in all four explain format:

Also, while I'm writing – it seems that somewhere next month, there will be 1 millionth plan uploaded to the site 🙂 Hope you all find it useful 🙂

Fix for displaying aggregates on

Couple of days ago RhodiumToad reported, on irc, a bug in

Specifically – if explain was done using JSON/XML/YAML formats, and node type was Aggregate, the site didn't extract full info.

Continue reading Fix for displaying aggregates on

Waiting for PostgreSQL 10 – Support XMLTABLE query expression

On 8th of March, Alvaro Herrera committed patch:

XMLTABLE is defined by the SQL/XML standard as a feature that allows
turning XML-formatted data into relational form, so that it can be used
as a <table primary> in the FROM clause of a query.
This new construct provides significant simplicity and performance
benefit for XML data processing; what in a client-side custom
implementation was reported to take 20 minutes can be executed in 400ms
using XMLTABLE.  (The same functionality was said to take 10 seconds
using nested PostgreSQL XPath function calls, and 5 seconds using
XMLReader under PL/Python).
The implemented syntax deviates slightly from what the standard
requires.  First, the standard indicates that the PASSING clause is
optional and that multiple XML input documents may be given to it; we
make it mandatory and accept a single document only.  Second, we don't
currently support a default namespace to be specified.
This implementation relies on a new executor node based on a hardcoded
method table.  (Because the grammar is fixed, there is no extensibility
in the current approach; further constructs can be implemented on top of
this such as JSON_TABLE, but they require changes to core code.)
Author: Pavel Stehule, Álvaro Herrera
Extensively reviewed by: Craig Ringer

Continue reading Waiting for PostgreSQL 10 – Support XMLTABLE query expression