Factored out database-specific date_trunc behavior into dbmod.get_date_trunc_sql(). Refs #46

git-svn-id: http://code.djangoproject.com/svn/django/trunk@161 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 6 insertions, 0 deletions

diff --git a/django/core/db/backends/postgresql.py b/django/core/db/backends/postgresql.py
index df7829f683..8a629453b3 100644
--- a/django/core/db/backends/postgresql.py
+++ b/django/core/db/backends/postgresql.py
@@ -63,8 +63,14 @@ def get_last_insert_id(cursor, table_name, pk_name):
 
 def get_date_extract_sql(lookup_type, table_name):
     # lookup_type is 'year', 'month', 'day'
+    # http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-EXTRACT
     return "EXTRACT('%s' FROM %s)" % (lookup_type, table_name)
 
+def get_date_trunc_sql(lookup_type, field_name):
+    # lookup_type is 'year', 'month', 'day'
+    # http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
+    return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
+
 # Register these custom typecasts, because Django expects dates/times to be
 # in Python's native (standard-library) datetime/time format, whereas psycopg
 # use mx.DateTime by default.