Refs #30897 -- Added support for ANALYZE option to Queryset.explain() on MariaDB and MySQL 8.0.18+.

This commit is contained in:
Nick Pope 2019-10-21 17:34:19 +01:00 committed by Mariusz Felisiak
parent 742961332e
commit 55df1750be
5 changed files with 40 additions and 8 deletions

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@ -117,6 +117,10 @@ class DatabaseFeatures(BaseDatabaseFeatures):
# EXTENDED is deprecated (and not required) in MySQL 5.7.
return not self.connection.mysql_is_mariadb and self.connection.mysql_version < (5, 7)
@cached_property
def supports_explain_analyze(self):
return self.connection.mysql_is_mariadb or self.connection.mysql_version >= (8, 0, 18)
@cached_property
def supported_explain_formats(self):
# Alias MySQL's TRADITIONAL to TEXT for consistency with other

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@ -299,11 +299,16 @@ class DatabaseOperations(BaseDatabaseOperations):
elif not format and 'TREE' in self.connection.features.supported_explain_formats:
# Use TREE by default (if supported) as it's more informative.
format = 'TREE'
analyze = options.pop('analyze', False)
prefix = super().explain_query_prefix(format, **options)
if format:
if analyze and self.connection.features.supports_explain_analyze:
# MariaDB uses ANALYZE instead of EXPLAIN ANALYZE.
prefix = 'ANALYZE' if self.connection.mysql_is_mariadb else prefix + ' ANALYZE'
if format and not (analyze and not self.connection.mysql_is_mariadb):
# Only MariaDB supports the analyze option with formats.
prefix += ' FORMAT=%s' % format
if self.connection.features.needs_explain_extended and format is None:
# EXTENDED and FORMAT are mutually exclusive options.
if self.connection.features.needs_explain_extended and not analyze and format is None:
# ANALYZE, EXTENDED, and FORMAT are mutually exclusive options.
prefix += ' EXTENDED'
return prefix

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@ -2587,13 +2587,14 @@ Pass these flags as keyword arguments. For example, when using PostgreSQL::
Execution time: 0.058 ms
On some databases, flags may cause the query to be executed which could have
adverse effects on your database. For example, PostgreSQL's ``ANALYZE`` flag
could result in changes to data if there are triggers or if a function is
called, even for a ``SELECT`` query.
adverse effects on your database. For example, the ``ANALYZE`` flag supported
by MariaDB, MySQL 8.0.18+, and PostgreSQL could result in changes to data if
there are triggers or if a function is called, even for a ``SELECT`` query.
.. versionchanged:: 3.1
Support for the ``'TREE'`` format on MySQL 8.0.16+ was added.
Support for the ``'TREE'`` format on MySQL 8.0.16+ and ``analyze`` option
on MariaDB and MySQL 8.0.18+ were added.
.. _field-lookups:

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@ -169,7 +169,10 @@ Models
:class:`~django.db.models.DateTimeField`, and the new :lookup:`iso_week_day`
lookup allows querying by an ISO-8601 day of week.
* :meth:`.QuerySet.explain` now supports ``TREE`` format on MySQL 8.0.16+.
* :meth:`.QuerySet.explain` now supports:
* ``TREE`` format on MySQL 8.0.16+,
* ``analyze`` option on MySQL 8.0.18+ and MariaDB.
Pagination
~~~~~~~~~~

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@ -80,6 +80,25 @@ class ExplainTests(TestCase):
self.assertEqual(len(captured_queries), 1)
self.assertIn('FORMAT=TRADITIONAL', captured_queries[0]['sql'])
@unittest.skipUnless(connection.vendor == 'mysql', 'MariaDB and MySQL >= 8.0.18 specific.')
def test_mysql_analyze(self):
# Inner skip to avoid module level query for MySQL version.
if not connection.features.supports_explain_analyze:
raise unittest.SkipTest('MariaDB and MySQL >= 8.0.18 specific.')
qs = Tag.objects.filter(name='test')
with CaptureQueriesContext(connection) as captured_queries:
qs.explain(analyze=True)
self.assertEqual(len(captured_queries), 1)
prefix = 'ANALYZE ' if connection.mysql_is_mariadb else 'EXPLAIN ANALYZE '
self.assertTrue(captured_queries[0]['sql'].startswith(prefix))
with CaptureQueriesContext(connection) as captured_queries:
qs.explain(analyze=True, format='JSON')
self.assertEqual(len(captured_queries), 1)
if connection.mysql_is_mariadb:
self.assertIn('FORMAT=JSON', captured_queries[0]['sql'])
else:
self.assertNotIn('FORMAT=JSON', captured_queries[0]['sql'])
@unittest.skipUnless(connection.vendor == 'mysql', 'MySQL < 5.7 specific')
def test_mysql_extended(self):
# Inner skip to avoid module level query for MySQL version.