570 lines
24 KiB
Python
570 lines
24 KiB
Python
import datetime
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import re
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import uuid
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from django.conf import settings
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from django.db.backends.base.operations import BaseDatabaseOperations
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from django.db.backends.utils import strip_quotes, truncate_name
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from django.utils import timezone
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from django.utils.encoding import force_bytes
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from .base import Database
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from .utils import BulkInsertMapper, InsertIdVar, Oracle_datetime
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class DatabaseOperations(BaseDatabaseOperations):
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# Oracle uses NUMBER(11) and NUMBER(19) for integer fields.
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integer_field_ranges = {
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'SmallIntegerField': (-99999999999, 99999999999),
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'IntegerField': (-99999999999, 99999999999),
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'BigIntegerField': (-9999999999999999999, 9999999999999999999),
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'PositiveSmallIntegerField': (0, 99999999999),
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'PositiveIntegerField': (0, 99999999999),
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}
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set_operators = dict(BaseDatabaseOperations.set_operators, difference='MINUS')
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# TODO: colorize this SQL code with style.SQL_KEYWORD(), etc.
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_sequence_reset_sql = """
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DECLARE
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table_value integer;
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seq_value integer;
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seq_name user_tab_identity_cols.sequence_name%%TYPE;
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BEGIN
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BEGIN
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SELECT sequence_name INTO seq_name FROM user_tab_identity_cols
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WHERE table_name = '%(table_name)s' AND
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column_name = '%(column_name)s';
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EXCEPTION WHEN NO_DATA_FOUND THEN
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seq_name := '%(no_autofield_sequence_name)s';
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END;
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SELECT NVL(MAX(%(column)s), 0) INTO table_value FROM %(table)s;
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SELECT NVL(last_number - cache_size, 0) INTO seq_value FROM user_sequences
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WHERE sequence_name = seq_name;
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WHILE table_value > seq_value LOOP
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EXECUTE IMMEDIATE 'SELECT "'||seq_name||'".nextval FROM DUAL'
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INTO seq_value;
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END LOOP;
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END;
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/"""
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# Oracle doesn't support string without precision; use the max string size.
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cast_char_field_without_max_length = 'NVARCHAR2(2000)'
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def cache_key_culling_sql(self):
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return """
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SELECT cache_key
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FROM (SELECT cache_key, rank() OVER (ORDER BY cache_key) AS rank FROM %s)
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WHERE rank = %%s + 1
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"""
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def date_extract_sql(self, lookup_type, field_name):
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if lookup_type == 'week_day':
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# TO_CHAR(field, 'D') returns an integer from 1-7, where 1=Sunday.
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return "TO_CHAR(%s, 'D')" % field_name
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elif lookup_type == 'week':
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# IW = ISO week number
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return "TO_CHAR(%s, 'IW')" % field_name
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elif lookup_type == 'quarter':
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return "TO_CHAR(%s, 'Q')" % field_name
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else:
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# https://docs.oracle.com/database/121/SQLRF/functions067.htm#SQLRF00639
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return "EXTRACT(%s FROM %s)" % (lookup_type.upper(), field_name)
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def date_interval_sql(self, timedelta):
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"""
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NUMTODSINTERVAL converts number to INTERVAL DAY TO SECOND literal.
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"""
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return "NUMTODSINTERVAL(%06f, 'SECOND')" % timedelta.total_seconds()
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def date_trunc_sql(self, lookup_type, field_name):
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# https://docs.oracle.com/database/121/SQLRF/functions271.htm#SQLRF52058
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if lookup_type in ('year', 'month'):
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return "TRUNC(%s, '%s')" % (field_name, lookup_type.upper())
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elif lookup_type == 'quarter':
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return "TRUNC(%s, 'Q')" % field_name
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else:
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return "TRUNC(%s)" % field_name
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# Oracle crashes with "ORA-03113: end-of-file on communication channel"
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# if the time zone name is passed in parameter. Use interpolation instead.
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# https://groups.google.com/forum/#!msg/django-developers/zwQju7hbG78/9l934yelwfsJ
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# This regexp matches all time zone names from the zoneinfo database.
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_tzname_re = re.compile(r'^[\w/:+-]+$')
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def _convert_field_to_tz(self, field_name, tzname):
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if not settings.USE_TZ:
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return field_name
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if not self._tzname_re.match(tzname):
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raise ValueError("Invalid time zone name: %s" % tzname)
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# Convert from UTC to local time, returning TIMESTAMP WITH TIME ZONE
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# and cast it back to TIMESTAMP to strip the TIME ZONE details.
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return "CAST((FROM_TZ(%s, '0:00') AT TIME ZONE '%s') AS TIMESTAMP)" % (field_name, tzname)
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def datetime_cast_date_sql(self, field_name, tzname):
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field_name = self._convert_field_to_tz(field_name, tzname)
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return 'TRUNC(%s)' % field_name
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def datetime_cast_time_sql(self, field_name, tzname):
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# Since `TimeField` values are stored as TIMESTAMP where only the date
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# part is ignored, convert the field to the specified timezone.
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return self._convert_field_to_tz(field_name, tzname)
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def datetime_extract_sql(self, lookup_type, field_name, tzname):
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field_name = self._convert_field_to_tz(field_name, tzname)
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return self.date_extract_sql(lookup_type, field_name)
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def datetime_trunc_sql(self, lookup_type, field_name, tzname):
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field_name = self._convert_field_to_tz(field_name, tzname)
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# https://docs.oracle.com/database/121/SQLRF/functions271.htm#SQLRF52058
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if lookup_type in ('year', 'month'):
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sql = "TRUNC(%s, '%s')" % (field_name, lookup_type.upper())
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elif lookup_type == 'quarter':
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sql = "TRUNC(%s, 'Q')" % field_name
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elif lookup_type == 'day':
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sql = "TRUNC(%s)" % field_name
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elif lookup_type == 'hour':
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sql = "TRUNC(%s, 'HH24')" % field_name
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elif lookup_type == 'minute':
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sql = "TRUNC(%s, 'MI')" % field_name
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else:
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sql = "CAST(%s AS DATE)" % field_name # Cast to DATE removes sub-second precision.
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return sql
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def time_trunc_sql(self, lookup_type, field_name):
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# The implementation is similar to `datetime_trunc_sql` as both
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# `DateTimeField` and `TimeField` are stored as TIMESTAMP where
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# the date part of the later is ignored.
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if lookup_type == 'hour':
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sql = "TRUNC(%s, 'HH24')" % field_name
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elif lookup_type == 'minute':
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sql = "TRUNC(%s, 'MI')" % field_name
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elif lookup_type == 'second':
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sql = "CAST(%s AS DATE)" % field_name # Cast to DATE removes sub-second precision.
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return sql
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def get_db_converters(self, expression):
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converters = super().get_db_converters(expression)
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internal_type = expression.output_field.get_internal_type()
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if internal_type == 'TextField':
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converters.append(self.convert_textfield_value)
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elif internal_type == 'BinaryField':
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converters.append(self.convert_binaryfield_value)
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elif internal_type in ['BooleanField', 'NullBooleanField']:
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converters.append(self.convert_booleanfield_value)
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elif internal_type == 'DateTimeField':
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converters.append(self.convert_datetimefield_value)
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elif internal_type == 'DateField':
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converters.append(self.convert_datefield_value)
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elif internal_type == 'TimeField':
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converters.append(self.convert_timefield_value)
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elif internal_type == 'UUIDField':
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converters.append(self.convert_uuidfield_value)
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# Oracle stores empty strings as null. If the field accepts the empty
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# string, undo this to adhere to the Django convention of using
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# the empty string instead of null.
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if expression.field.empty_strings_allowed:
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converters.append(
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self.convert_empty_bytes
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if internal_type == 'BinaryField' else
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self.convert_empty_string
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)
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return converters
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def convert_textfield_value(self, value, expression, connection):
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if isinstance(value, Database.LOB):
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value = value.read()
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return value
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def convert_binaryfield_value(self, value, expression, connection):
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if isinstance(value, Database.LOB):
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value = force_bytes(value.read())
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return value
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def convert_booleanfield_value(self, value, expression, connection):
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if value in (0, 1):
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value = bool(value)
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return value
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# cx_Oracle always returns datetime.datetime objects for
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# DATE and TIMESTAMP columns, but Django wants to see a
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# python datetime.date, .time, or .datetime.
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def convert_datetimefield_value(self, value, expression, connection):
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if value is not None:
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if settings.USE_TZ:
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value = timezone.make_aware(value, self.connection.timezone)
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return value
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def convert_datefield_value(self, value, expression, connection):
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if isinstance(value, Database.Timestamp):
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value = value.date()
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return value
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def convert_timefield_value(self, value, expression, connection):
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if isinstance(value, Database.Timestamp):
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value = value.time()
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return value
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def convert_uuidfield_value(self, value, expression, connection):
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if value is not None:
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value = uuid.UUID(value)
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return value
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@staticmethod
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def convert_empty_string(value, expression, connection):
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return '' if value is None else value
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@staticmethod
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def convert_empty_bytes(value, expression, connection):
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return b'' if value is None else value
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def deferrable_sql(self):
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return " DEFERRABLE INITIALLY DEFERRED"
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def fetch_returned_insert_id(self, cursor):
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return int(cursor._insert_id_var.getvalue())
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def field_cast_sql(self, db_type, internal_type):
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if db_type and db_type.endswith('LOB'):
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return "DBMS_LOB.SUBSTR(%s)"
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else:
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return "%s"
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def no_limit_value(self):
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return None
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def limit_offset_sql(self, low_mark, high_mark):
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fetch, offset = self._get_limit_offset_params(low_mark, high_mark)
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return '%s%s' % (
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(' OFFSET %d ROWS' % offset) if offset else '',
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(' FETCH FIRST %d ROWS ONLY' % fetch) if fetch else '',
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)
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def last_executed_query(self, cursor, sql, params):
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# https://cx-oracle.readthedocs.io/en/latest/cursor.html#Cursor.statement
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# The DB API definition does not define this attribute.
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statement = cursor.statement
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# Unlike Psycopg's `query` and MySQLdb`'s `_last_executed`, CxOracle's
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# `statement` doesn't contain the query parameters. refs #20010.
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return super().last_executed_query(cursor, statement, params)
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def last_insert_id(self, cursor, table_name, pk_name):
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sq_name = self._get_sequence_name(cursor, strip_quotes(table_name), pk_name)
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cursor.execute('"%s".currval' % sq_name)
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return cursor.fetchone()[0]
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def lookup_cast(self, lookup_type, internal_type=None):
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if lookup_type in ('iexact', 'icontains', 'istartswith', 'iendswith'):
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return "UPPER(%s)"
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return "%s"
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def max_in_list_size(self):
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return 1000
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def max_name_length(self):
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return 30
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def pk_default_value(self):
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return "NULL"
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def prep_for_iexact_query(self, x):
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return x
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def process_clob(self, value):
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if value is None:
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return ''
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return value.read()
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def quote_name(self, name):
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# SQL92 requires delimited (quoted) names to be case-sensitive. When
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# not quoted, Oracle has case-insensitive behavior for identifiers, but
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# always defaults to uppercase.
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# We simplify things by making Oracle identifiers always uppercase.
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if not name.startswith('"') and not name.endswith('"'):
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name = '"%s"' % truncate_name(name.upper(), self.max_name_length())
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# Oracle puts the query text into a (query % args) construct, so % signs
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# in names need to be escaped. The '%%' will be collapsed back to '%' at
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# that stage so we aren't really making the name longer here.
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name = name.replace('%', '%%')
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return name.upper()
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def random_function_sql(self):
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return "DBMS_RANDOM.RANDOM"
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def regex_lookup(self, lookup_type):
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if lookup_type == 'regex':
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match_option = "'c'"
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else:
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match_option = "'i'"
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return 'REGEXP_LIKE(%%s, %%s, %s)' % match_option
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def return_insert_id(self):
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return "RETURNING %s INTO %%s", (InsertIdVar(),)
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def savepoint_create_sql(self, sid):
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return "SAVEPOINT " + self.quote_name(sid)
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def savepoint_rollback_sql(self, sid):
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return "ROLLBACK TO SAVEPOINT " + self.quote_name(sid)
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def _foreign_key_constraints(self, table_name, recursive=False):
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with self.connection.cursor() as cursor:
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if recursive:
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cursor.execute("""
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SELECT
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user_tables.table_name, rcons.constraint_name
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FROM
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user_tables
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JOIN
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user_constraints cons
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ON (user_tables.table_name = cons.table_name AND cons.constraint_type = ANY('P', 'U'))
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LEFT JOIN
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user_constraints rcons
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ON (user_tables.table_name = rcons.table_name AND rcons.constraint_type = 'R')
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START WITH user_tables.table_name = UPPER(%s)
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CONNECT BY NOCYCLE PRIOR cons.constraint_name = rcons.r_constraint_name
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GROUP BY
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user_tables.table_name, rcons.constraint_name
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HAVING user_tables.table_name != UPPER(%s)
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ORDER BY MAX(level) DESC
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""", (table_name, table_name))
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else:
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cursor.execute("""
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SELECT
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cons.table_name, cons.constraint_name
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FROM
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user_constraints cons
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WHERE
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cons.constraint_type = 'R'
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AND cons.table_name = UPPER(%s)
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""", (table_name,))
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return cursor.fetchall()
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def sql_flush(self, style, tables, sequences, allow_cascade=False):
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if tables:
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truncated_tables = {table.upper() for table in tables}
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constraints = set()
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# Oracle's TRUNCATE CASCADE only works with ON DELETE CASCADE
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# foreign keys which Django doesn't define. Emulate the
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# PostgreSQL behavior which truncates all dependent tables by
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# manually retrieving all foreign key constraints and resolving
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# dependencies.
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for table in tables:
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for foreign_table, constraint in self._foreign_key_constraints(table, recursive=allow_cascade):
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if allow_cascade:
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truncated_tables.add(foreign_table)
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constraints.add((foreign_table, constraint))
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sql = [
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"%s %s %s %s %s %s %s %s;" % (
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style.SQL_KEYWORD('ALTER'),
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style.SQL_KEYWORD('TABLE'),
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style.SQL_FIELD(self.quote_name(table)),
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style.SQL_KEYWORD('DISABLE'),
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style.SQL_KEYWORD('CONSTRAINT'),
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style.SQL_FIELD(self.quote_name(constraint)),
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style.SQL_KEYWORD('KEEP'),
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style.SQL_KEYWORD('INDEX'),
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) for table, constraint in constraints
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] + [
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"%s %s %s;" % (
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style.SQL_KEYWORD('TRUNCATE'),
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style.SQL_KEYWORD('TABLE'),
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style.SQL_FIELD(self.quote_name(table)),
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) for table in truncated_tables
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] + [
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"%s %s %s %s %s %s;" % (
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style.SQL_KEYWORD('ALTER'),
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style.SQL_KEYWORD('TABLE'),
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style.SQL_FIELD(self.quote_name(table)),
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style.SQL_KEYWORD('ENABLE'),
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style.SQL_KEYWORD('CONSTRAINT'),
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style.SQL_FIELD(self.quote_name(constraint)),
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) for table, constraint in constraints
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]
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# Since we've just deleted all the rows, running our sequence
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# ALTER code will reset the sequence to 0.
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sql.extend(self.sequence_reset_by_name_sql(style, sequences))
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return sql
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else:
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return []
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def sequence_reset_by_name_sql(self, style, sequences):
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sql = []
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for sequence_info in sequences:
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no_autofield_sequence_name = self._get_no_autofield_sequence_name(sequence_info['table'])
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table = self.quote_name(sequence_info['table'])
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column = self.quote_name(sequence_info['column'] or 'id')
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query = self._sequence_reset_sql % {
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'no_autofield_sequence_name': no_autofield_sequence_name,
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'table': table,
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'column': column,
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'table_name': strip_quotes(table),
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'column_name': strip_quotes(column),
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}
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sql.append(query)
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return sql
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def sequence_reset_sql(self, style, model_list):
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from django.db import models
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output = []
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query = self._sequence_reset_sql
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for model in model_list:
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for f in model._meta.local_fields:
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if isinstance(f, models.AutoField):
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no_autofield_sequence_name = self._get_no_autofield_sequence_name(model._meta.db_table)
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table = self.quote_name(model._meta.db_table)
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column = self.quote_name(f.column)
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output.append(query % {
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'no_autofield_sequence_name': no_autofield_sequence_name,
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'table': table,
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'column': column,
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'table_name': strip_quotes(table),
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'column_name': strip_quotes(column),
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})
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# Only one AutoField is allowed per model, so don't
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# continue to loop
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break
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for f in model._meta.many_to_many:
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if not f.remote_field.through:
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no_autofield_sequence_name = self._get_no_autofield_sequence_name(f.m2m_db_table())
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table = self.quote_name(f.m2m_db_table())
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column = self.quote_name('id')
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output.append(query % {
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'no_autofield_sequence_name': no_autofield_sequence_name,
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'table': table,
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'column': column,
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'table_name': strip_quotes(table),
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'column_name': 'ID',
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})
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return output
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def start_transaction_sql(self):
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return ''
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def tablespace_sql(self, tablespace, inline=False):
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if inline:
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return "USING INDEX TABLESPACE %s" % self.quote_name(tablespace)
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else:
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return "TABLESPACE %s" % self.quote_name(tablespace)
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def adapt_datefield_value(self, value):
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"""
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Transform a date value to an object compatible with what is expected
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by the backend driver for date columns.
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The default implementation transforms the date to text, but that is not
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necessary for Oracle.
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"""
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return value
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def adapt_datetimefield_value(self, value):
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"""
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Transform a datetime value to an object compatible with what is expected
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by the backend driver for datetime columns.
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If naive datetime is passed assumes that is in UTC. Normally Django
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models.DateTimeField makes sure that if USE_TZ is True passed datetime
|
|
is timezone aware.
|
|
"""
|
|
|
|
if value is None:
|
|
return None
|
|
|
|
# Expression values are adapted by the database.
|
|
if hasattr(value, 'resolve_expression'):
|
|
return value
|
|
|
|
# cx_Oracle doesn't support tz-aware datetimes
|
|
if timezone.is_aware(value):
|
|
if settings.USE_TZ:
|
|
value = timezone.make_naive(value, self.connection.timezone)
|
|
else:
|
|
raise ValueError("Oracle backend does not support timezone-aware datetimes when USE_TZ is False.")
|
|
|
|
return Oracle_datetime.from_datetime(value)
|
|
|
|
def adapt_timefield_value(self, value):
|
|
if value is None:
|
|
return None
|
|
|
|
# Expression values are adapted by the database.
|
|
if hasattr(value, 'resolve_expression'):
|
|
return value
|
|
|
|
if isinstance(value, str):
|
|
return datetime.datetime.strptime(value, '%H:%M:%S')
|
|
|
|
# Oracle doesn't support tz-aware times
|
|
if timezone.is_aware(value):
|
|
raise ValueError("Oracle backend does not support timezone-aware times.")
|
|
|
|
return Oracle_datetime(1900, 1, 1, value.hour, value.minute,
|
|
value.second, value.microsecond)
|
|
|
|
def combine_expression(self, connector, sub_expressions):
|
|
lhs, rhs = sub_expressions
|
|
if connector == '%%':
|
|
return 'MOD(%s)' % ','.join(sub_expressions)
|
|
elif connector == '&':
|
|
return 'BITAND(%s)' % ','.join(sub_expressions)
|
|
elif connector == '|':
|
|
return 'BITAND(-%(lhs)s-1,%(rhs)s)+%(lhs)s' % {'lhs': lhs, 'rhs': rhs}
|
|
elif connector == '<<':
|
|
return '(%(lhs)s * POWER(2, %(rhs)s))' % {'lhs': lhs, 'rhs': rhs}
|
|
elif connector == '>>':
|
|
return 'FLOOR(%(lhs)s / POWER(2, %(rhs)s))' % {'lhs': lhs, 'rhs': rhs}
|
|
elif connector == '^':
|
|
return 'POWER(%s)' % ','.join(sub_expressions)
|
|
return super().combine_expression(connector, sub_expressions)
|
|
|
|
def _get_no_autofield_sequence_name(self, table):
|
|
"""
|
|
Manually created sequence name to keep backward compatibility for
|
|
AutoFields that aren't Oracle identity columns.
|
|
"""
|
|
name_length = self.max_name_length() - 3
|
|
return '%s_SQ' % truncate_name(strip_quotes(table), name_length).upper()
|
|
|
|
def _get_sequence_name(self, cursor, table, pk_name):
|
|
cursor.execute("""
|
|
SELECT sequence_name
|
|
FROM user_tab_identity_cols
|
|
WHERE table_name = UPPER(%s)
|
|
AND column_name = UPPER(%s)""", [table, pk_name])
|
|
row = cursor.fetchone()
|
|
return self._get_no_autofield_sequence_name(table) if row is None else row[0]
|
|
|
|
def bulk_insert_sql(self, fields, placeholder_rows):
|
|
query = []
|
|
for row in placeholder_rows:
|
|
select = []
|
|
for i, placeholder in enumerate(row):
|
|
# A model without any fields has fields=[None].
|
|
if fields[i]:
|
|
internal_type = getattr(fields[i], 'target_field', fields[i]).get_internal_type()
|
|
placeholder = BulkInsertMapper.types.get(internal_type, '%s') % placeholder
|
|
# Add columns aliases to the first select to avoid "ORA-00918:
|
|
# column ambiguously defined" when two or more columns in the
|
|
# first select have the same value.
|
|
if not query:
|
|
placeholder = '%s col_%s' % (placeholder, i)
|
|
select.append(placeholder)
|
|
query.append('SELECT %s FROM DUAL' % ', '.join(select))
|
|
# Bulk insert to tables with Oracle identity columns causes Oracle to
|
|
# add sequence.nextval to it. Sequence.nextval cannot be used with the
|
|
# UNION operator. To prevent incorrect SQL, move UNION to a subquery.
|
|
return 'SELECT * FROM (%s)' % ' UNION ALL '.join(query)
|
|
|
|
def subtract_temporals(self, internal_type, lhs, rhs):
|
|
if internal_type == 'DateField':
|
|
lhs_sql, lhs_params = lhs
|
|
rhs_sql, rhs_params = rhs
|
|
return "NUMTODSINTERVAL(%s - %s, 'DAY')" % (lhs_sql, rhs_sql), lhs_params + rhs_params
|
|
return super().subtract_temporals(internal_type, lhs, rhs)
|
|
|
|
def bulk_batch_size(self, fields, objs):
|
|
"""Oracle restricts the number of parameters in a query."""
|
|
if fields:
|
|
return self.connection.features.max_query_params // len(fields)
|
|
return len(objs)
|