Debugging SQL

Debugging SQL in code

You can have Pootle output the SQL calls that are created by sections of code:

from pootle.core.debug import debug_sql
with debug_sql():
   trigger_some_sql()

It is worth remembering that Django querysets are evaluated lazily, so you might need to manually trigger the call:

with debug_sql():
   [x for x in trigger_some_sql()]

Debugging tests

When running Pootle tests you can see a count of the database calls that were made for each test, and some overall test metrics.

py.test -vv --debug-tests mytest.log

This can be used with the -k flag so you can test a subset of the test suite for db performance.

For example to test performance of update related code

py.test -vv -k update --debug-tests mytest.log

Debugging information for the test run is appended to the specified file. You can watch the debugging with

tail -f mytest.log