id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
7420	Further generalization of DB backend (mis)features	Ramiro Morales	Adrian Holovaty	"The patch attached:

 * Adds four new atttibutes to !DatabaseFeatures (also setting the correct values for the backends bundled with Django):

{{{
#!python
supports_usecs # default value: True
time_field_needs_date # default value: False
interprets_empty_strings_as_nulls # default value: False
date_field_supports_time_value # default value: True
}}}

 * Moves {{{prep_for_like_query}}} from a global lambda form at {{{django/db/backends/__init__.py}}}) to a method of !DatabaseOperations

 * Modifies {{{contrib/sessions/backends/db.py}}} and {{{django/db/models/fields/__init__.py}}} to use them instead of tests of the style {{{if settings.DATABASE_BACKEND == 'oracle':...}}}.

If I understand things correctly this is a desirable thing to have.

Additionally this would allow moving forward with a MS SQL Server (that shares one trait with Oracle and another with MySQL and that  has a particular LIKE query syntax) as a truly external backends i.e. reducing the need to patch Django itself to a minimum.

Tested with the Django trunk test suite on a Debian Etch -based environment:

 * pysqlite2 2.3.2 + sqlite 3.3.8
 * MySQLdb 1.2.1 + MySQL 5.0.32
 * psycopg2 2.0.5 + PostgreSQL 8.1.11

(no Oracle installation at hand :( but hopefully somebody will be able test with that backend and report below)"		closed	Database layer (models, ORM)	dev		fixed	databasefeatures database operations microseconds oracle mysql		Accepted	1	0	0	0	0	0