boulder-oracle-sprint: Refactored all Oracle references outside django.db into the

backend.


git-svn-id: http://code.djangoproject.com/svn/django/branches/boulder-oracle-sprint@4082 bcc190cf-cafb-0310-a4f2-bffc1f526a37

7 files changed, 90 insertions, 30 deletions

diff --git a/django/db/backends/ado_mssql/base.py b/django/db/backends/ado_mssql/base.py
index ad1f6dd60f..33800980a8 100644
--- a/django/db/backends/ado_mssql/base.py
+++ b/django/db/backends/ado_mssql/base.py
@@ -87,6 +87,9 @@ class DatabaseWrapper(local):
             self.connection.close()
             self.connection = None
 
+allows_group_by_ordinal = True
+allows_unique_and_pk = True
+returns_dates_as_strings = False
 supports_constraints = True
 uses_case_insensitive_names = False
 
@@ -116,6 +119,9 @@ def get_date_trunc_sql(lookup_type, field_name):
     if lookup_type=='day':
         return "Convert(datetime, Convert(varchar(12), %s))" % field_name
 
+def get_datetime_cast_sql():
+    return None
+
 def get_limit_offset_sql(limit, offset=None):
     # TODO: This is a guess. Make sure this is correct.
     sql = "LIMIT %s" % limit
@@ -138,6 +144,9 @@ def get_pk_default_value():
 def get_max_name_length():
     return None
 
+def get_autoinc_sql(table):
+    return None
+
 OPERATOR_MAPPING = {
     'exact': '= %s',
     'iexact': 'LIKE %s',
diff --git a/django/db/backends/mysql/base.py b/django/db/backends/mysql/base.py
index 0dd73ac51a..e5756dc4b0 100644
--- a/django/db/backends/mysql/base.py
+++ b/django/db/backends/mysql/base.py
@@ -130,6 +130,9 @@ class DatabaseWrapper(local):
             self.server_version = tuple([int(x) for x in m.groups()])
         return self.server_version
 
+allows_group_by_ordinal = True
+allows_unique_and_pk = True
+returns_dates_as_strings = True     # MySQLdb requires a typecast for dates
 supports_constraints = True
 uses_case_insensitive_names = False
 
@@ -164,6 +167,9 @@ def get_date_trunc_sql(lookup_type, field_name):
         sql = "CAST(DATE_FORMAT(%s, '%s') AS DATETIME)" % (field_name, format_str)
     return sql
 
+def get_datetime_cast_sql():
+    return None
+
 def get_limit_offset_sql(limit, offset=None):
     sql = "LIMIT "
     if offset and offset != 0:
@@ -185,6 +191,9 @@ def get_pk_default_value():
 def get_max_name_length():
     return 64;
 
+def get_autoinc_sql(table):
+    return None
+
 OPERATOR_MAPPING = {
     'exact': '= %s',
     'iexact': 'LIKE %s',
diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py
index 5831ca47da..4e6314d32e 100644
--- a/django/db/backends/oracle/base.py
+++ b/django/db/backends/oracle/base.py
@@ -59,6 +59,9 @@ class DatabaseWrapper(local):
             self.connection.close()
             self.connection = None
 
+allows_group_by_ordinal = False
+allows_unique_and_pk = False        # Suppress UNIQUE/PK for Oracle (ORA-02259)
+returns_dates_as_strings = False
 supports_constraints = True
 uses_case_insensitive_names = True
 
@@ -118,6 +121,9 @@ def get_date_trunc_sql(lookup_type, field_name):
         sql = "TRUNC(%s, '%s')" % (field_name, lookup_type)
     return sql
 
+def get_datetime_cast_sql():
+    return "TO_TIMESTAMP(%s, 'YYYY-MM-DD HH24:MI:SS')"
+
 def get_limit_offset_sql(limit, offset=None):
     # Limits and offset are too complicated to be handled here.
     # Instead, they are handled in django/db/backends/oracle/query.py.
@@ -138,11 +144,27 @@ def get_pk_default_value():
 def get_max_name_length():
     return 30
 
+def get_autoinc_sql(table):
+    # To simulate auto-incrementing primary keys in Oracle, we have to
+    # create a sequence and a trigger.
+    name_length = get_max_name_length() - 3
+    sq_name = '%s_sq' % util.truncate_name(table, name_length)
+    tr_name = '%s_tr' % util.truncate_name(table, name_length)
+    sequence_sql = 'CREATE SEQUENCE %s;' % sq_name
+    trigger_sql = """CREATE OR REPLACE TRIGGER %s
+  BEFORE INSERT ON %s
+  FOR EACH ROW
+  WHEN (new.id IS NULL)
+    BEGIN
+      SELECT %s.nextval INTO :new.id FROM dual;
+    END;\n""" % (tr_name, quote_name(table), sq_name)
+    return sequence_sql, trigger_sql
+
 OPERATOR_MAPPING = {
     'exact': '= %s',
     'iexact': "LIKE %s ESCAPE '\\'",
     'contains': "LIKE %s ESCAPE '\\'",
-    'icontains': "LIKE %s ESCAPE '\\'",
+    'icontains': "LIKE LOWER(%s) ESCAPE '\\'",
     'gt': '> %s',
     'gte': '>= %s',
     'lt': '< %s',
diff --git a/django/db/backends/postgresql/base.py b/django/db/backends/postgresql/base.py
index 1fba77a550..fd3ef87c45 100644
--- a/django/db/backends/postgresql/base.py
+++ b/django/db/backends/postgresql/base.py
@@ -61,6 +61,9 @@ class DatabaseWrapper(local):
             self.connection.close()
             self.connection = None
 
+allows_group_by_ordinal = True
+allows_unique_and_pk = True
+returns_dates_as_strings = False
 supports_constraints = True
 uses_case_insensitive_names = False
 
@@ -95,6 +98,9 @@ def get_date_trunc_sql(lookup_type, field_name):
     # http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
     return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
 
+def get_datetime_cast_sql():
+    return None
+
 def get_limit_offset_sql(limit, offset=None):
     sql = "LIMIT %s" % limit
     if offset and offset != 0:
@@ -116,6 +122,9 @@ def get_pk_default_value():
 def get_max_name_length():
     return None
 
+def get_autoinc_sql(table):
+    return None
+
 # 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.
diff --git a/django/db/backends/postgresql_psycopg2/base.py b/django/db/backends/postgresql_psycopg2/base.py
index bfbb7616db..b2722d8d99 100644
--- a/django/db/backends/postgresql_psycopg2/base.py
+++ b/django/db/backends/postgresql_psycopg2/base.py
@@ -62,6 +62,9 @@ class DatabaseWrapper(local):
             self.connection.close()
             self.connection = None
 
+allows_group_by_ordinal = True
+allows_unique_and_pk = True
+returns_dates_as_strings = False
 supports_constraints = True
 uses_case_insensitive_names = True
 
@@ -88,6 +91,9 @@ def get_date_trunc_sql(lookup_type, field_name):
     # http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
     return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
 
+def get_datetime_cast_sql():
+    return None
+
 def get_limit_offset_sql(limit, offset=None):
     sql = "LIMIT %s" % limit
     if offset and offset != 0:
@@ -109,6 +115,9 @@ def get_pk_default_value():
 def get_max_name_length():
     return None
 
+def get_autoinc_sql(table):
+    return None
+
 OPERATOR_MAPPING = {
     'exact': '= %s',
     'iexact': 'ILIKE %s',
diff --git a/django/db/backends/sqlite3/base.py b/django/db/backends/sqlite3/base.py
index cc27bb0a1c..c92e83a6ad 100644
--- a/django/db/backends/sqlite3/base.py
+++ b/django/db/backends/sqlite3/base.py
@@ -98,6 +98,9 @@ class SQLiteCursorWrapper(Database.Cursor):
     def convert_query(self, query, num_params):
         return query % tuple("?" * num_params)
 
+allows_group_by_ordinal = True
+allows_unique_and_pk = True
+returns_dates_as_strings = True
 supports_constraints = False
 uses_case_insensitive_names = False
 
@@ -131,6 +134,9 @@ def get_date_trunc_sql(lookup_type, field_name):
     # sqlite doesn't support DATE_TRUNC, so we fake it as above.
     return 'django_date_trunc("%s", %s)' % (lookup_type.lower(), field_name)
 
+def get_datetime_cast_sql():
+    return None
+
 def get_limit_offset_sql(limit, offset=None):
     sql = "LIMIT %s" % limit
     if offset and offset != 0:
@@ -152,6 +158,9 @@ def get_pk_default_value():
 def get_max_name_length():
     return None
 
+def get_autoinc_sql(table):
+    return None
+
 def _sqlite_date_trunc(lookup_type, dt):
     try:
         dt = util.typecast_timestamp(dt)
diff --git a/django/db/models/query.py b/django/db/models/query.py
index 847906fd26..53a17c23d7 100644
--- a/django/db/models/query.py
+++ b/django/db/models/query.py
@@ -1,5 +1,4 @@
-from django import db
-from django.db import backend, connection, transaction
+from django.db import backend, connection, get_query_module, transaction
 from django.db.models.fields import DateField, FieldDoesNotExist
 from django.db.models import signals
 from django.dispatch import dispatcher
@@ -509,13 +508,12 @@ class _QuerySet(object):
         else:
             assert self._offset is None, "'offset' is not allowed without 'limit'"
 
-        return select, " ".join(sql), params
+        return select, " ".join(sql), params, None
 
-# Check to see if the DB backend would like to define its own QuerySet class
-# and otherwise use the default.
-backend_query_module = db.get_query_module()
-if hasattr(backend_query_module, "get_query_set_class"):
-    QuerySet = db.get_query_module().get_query_set_class(_QuerySet)
+# Use the backend's QuerySet class if it defines one, otherwise use _QuerySet.
+backend_query_module = get_query_module()
+if hasattr(backend_query_module, 'get_query_set_class'):
+    QuerySet = backend_query_module.get_query_set_class(_QuerySet)
 else:
     QuerySet = _QuerySet
 
@@ -561,21 +559,18 @@ class DateQuerySet(QuerySet):
         field_name = backend.quote_name(self._field.column)
         date_trunc_sql = backend.get_date_trunc_sql(self._kind,
                                                     '%s.%s' % (table_name, field_name))
-        fmt = 'SELECT %s %s GROUP BY %s ORDER BY 1 %s'
-
-        if settings.DATABASE_ENGINE == 'oracle':
-            sql = fmt % (date_trunc_sql, sql, date_trunc_sql, self._order)
-            cursor = connection.cursor()
-            cursor.execute(sql, params)
-            return [row[0] for row in cursor.fetchall()]
+        if backend.allows_group_by_ordinal:
+            group_by = '1'
         else:
-            sql = fmt % (date_trunc_sql, sql, 1, self._order_by)
-            cursor = connection.cursor()
-            cursor.execute(sql, params)
-            # We have to manually run typecast_timestamp(str()) on the results, because
-            # MySQL doesn't automatically cast the result of date functions as datetime
-            # objects -- MySQL returns the values as strings, instead.
+            group_by = date_trunc_sql
+        fmt = 'SELECT %s %s GROUP BY %s ORDER BY 1 %s'
+        stmt = fmt % (date_trunc_sql, sql, group_by, self._order)
+        cursor = connection.cursor()
+        cursor.execute(stmt, params)
+        if backend.returns_dates_as_strings:
             return [typecast_timestamp(str(row[0])) for row in cursor.fetchall()]
+        else:
+            return [row[0] for row in cursor.fetchall()]
 
     def _clone(self, klass=None, **kwargs):
         c = super(DateQuerySet, self)._clone(klass, **kwargs)
@@ -657,15 +652,13 @@ def get_where_clause(lookup_type, table_prefix, field_name, value):
     if table_prefix.endswith('.'):
         table_prefix = backend.quote_name(table_prefix[:-1])+'.'
     field_name = backend.quote_name(field_name)
-    # TODO: move this into django.db.backends.oracle somehow
-    if settings.DATABASE_ENGINE == 'oracle':
-        if lookup_type == 'icontains':
-            return 'lower(%s%s) %s' % (table_prefix, field_name, (backend.OPERATOR_MAPPING[lookup_type] % '%s'))
-        elif type(value) == datetime.datetime:
-            return "%s%s %s" % (table_prefix, field_name,
-                 (backend.OPERATOR_MAPPING[lookup_type] % "TO_TIMESTAMP(%s, 'YYYY-MM-DD HH24:MI:SS')"))
+    if type(value) == datetime.datetime and backend.get_datetime_cast_sql():
+        cast_sql = backend.get_datetime_cast_sql()
+    else:
+        cast_sql = '%s'
     try:
-        return '%s%s %s' % (table_prefix, field_name, (backend.OPERATOR_MAPPING[lookup_type] % '%s'))
+        return '%s%s %s' % (table_prefix, field_name,
+                            backend.OPERATOR_MAPPING[lookup_type] % cast_sql)
     except KeyError:
         pass
     if lookup_type == 'in':