pg_plan_tree_dot is a PostgreSQL extension which visualizes a plan tree using Graphviz.

As you know, the EXPLAIN command displays the execution plan that PostgreSQL's planner/optimizer generates for the supplied statement. However the result of this command is rough.

pg_plan_tree_dot allows you to generate a .dot file from the given SQL query, and then you convert the ouput .dot file into the plan tree graph using the "dot" command for Graphviz.

Requirements

• Install Graphviz
• Install PostgreSQL 9.x

Tested on:

• PostgreSQL 9.0.23, 9.1.23, 9.2.18, 9.3.14, 9.4.9, 9.5.4, 9.6.18, 10.13, 11.8 and 12.3 under x86-64 CentOS 7.x

Building

First, acquire the source code by cloning the git repository.

git clone https://github.com/nminoru/pg_plan_tree_dot

Next, input the following commadns.

cd pg_plan_tree_dot
make
make install

Usage

CREATE EXTENSION pg_plan_tree_dot;
SELECT generate_plan_tree_dot('sql', 'output.dot');

dot -Tpng output.dot -o output.png