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Diffstat (limited to 'webapp/django/db/backends/mysql/base.py')
| -rw-r--r-- | webapp/django/db/backends/mysql/base.py | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/webapp/django/db/backends/mysql/base.py b/webapp/django/db/backends/mysql/base.py new file mode 100644 index 0000000000..07fb700eaa --- /dev/null +++ b/webapp/django/db/backends/mysql/base.py @@ -0,0 +1,227 @@ +""" +MySQL database backend for Django. + +Requires MySQLdb: http://sourceforge.net/projects/mysql-python +""" + +import re + +try: + import MySQLdb as Database +except ImportError, e: + from django.core.exceptions import ImproperlyConfigured + raise ImproperlyConfigured("Error loading MySQLdb module: %s" % e) + +# We want version (1, 2, 1, 'final', 2) or later. We can't just use +# lexicographic ordering in this check because then (1, 2, 1, 'gamma') +# inadvertently passes the version test. +version = Database.version_info +if (version < (1,2,1) or (version[:3] == (1, 2, 1) and + (len(version) < 5 or version[3] != 'final' or version[4] < 2))): + from django.core.exceptions import ImproperlyConfigured + raise ImproperlyConfigured("MySQLdb-1.2.1p2 or newer is required; you have %s" % Database.__version__) + +from MySQLdb.converters import conversions +from MySQLdb.constants import FIELD_TYPE, FLAG + +from django.db.backends import * +from django.db.backends.mysql.client import DatabaseClient +from django.db.backends.mysql.creation import DatabaseCreation +from django.db.backends.mysql.introspection import DatabaseIntrospection +from django.db.backends.mysql.validation import DatabaseValidation + +# Raise exceptions for database warnings if DEBUG is on +from django.conf import settings +if settings.DEBUG: + from warnings import filterwarnings + filterwarnings("error", category=Database.Warning) + +DatabaseError = Database.DatabaseError +IntegrityError = Database.IntegrityError + +# MySQLdb-1.2.1 supports the Python boolean type, and only uses datetime +# module for time-related columns; older versions could have used mx.DateTime +# or strings if there were no datetime module. However, MySQLdb still returns +# TIME columns as timedelta -- they are more like timedelta in terms of actual +# behavior as they are signed and include days -- and Django expects time, so +# we still need to override that. +django_conversions = conversions.copy() +django_conversions.update({ + FIELD_TYPE.TIME: util.typecast_time, + FIELD_TYPE.DECIMAL: util.typecast_decimal, + FIELD_TYPE.NEWDECIMAL: util.typecast_decimal, +}) + +# This should match the numerical portion of the version numbers (we can treat +# versions like 5.0.24 and 5.0.24a as the same). Based on the list of version +# at http://dev.mysql.com/doc/refman/4.1/en/news.html and +# http://dev.mysql.com/doc/refman/5.0/en/news.html . +server_version_re = re.compile(r'(\d{1,2})\.(\d{1,2})\.(\d{1,2})') + +# MySQLdb-1.2.1 and newer automatically makes use of SHOW WARNINGS on +# MySQL-4.1 and newer, so the MysqlDebugWrapper is unnecessary. Since the +# point is to raise Warnings as exceptions, this can be done with the Python +# warning module, and this is setup when the connection is created, and the +# standard util.CursorDebugWrapper can be used. Also, using sql_mode +# TRADITIONAL will automatically cause most warnings to be treated as errors. + +class DatabaseFeatures(BaseDatabaseFeatures): + empty_fetchmany_value = () + update_can_self_select = False + +class DatabaseOperations(BaseDatabaseOperations): + def date_extract_sql(self, lookup_type, field_name): + # http://dev.mysql.com/doc/mysql/en/date-and-time-functions.html + return "EXTRACT(%s FROM %s)" % (lookup_type.upper(), field_name) + + def date_trunc_sql(self, lookup_type, field_name): + fields = ['year', 'month', 'day', 'hour', 'minute', 'second'] + format = ('%%Y-', '%%m', '-%%d', ' %%H:', '%%i', ':%%s') # Use double percents to escape. + format_def = ('0000-', '01', '-01', ' 00:', '00', ':00') + try: + i = fields.index(lookup_type) + 1 + except ValueError: + sql = field_name + else: + format_str = ''.join([f for f in format[:i]] + [f for f in format_def[i:]]) + sql = "CAST(DATE_FORMAT(%s, '%s') AS DATETIME)" % (field_name, format_str) + return sql + + def drop_foreignkey_sql(self): + return "DROP FOREIGN KEY" + + def fulltext_search_sql(self, field_name): + return 'MATCH (%s) AGAINST (%%s IN BOOLEAN MODE)' % field_name + + def no_limit_value(self): + # 2**64 - 1, as recommended by the MySQL documentation + return 18446744073709551615L + + def quote_name(self, name): + if name.startswith("`") and name.endswith("`"): + return name # Quoting once is enough. + return "`%s`" % name + + def random_function_sql(self): + return 'RAND()' + + def sql_flush(self, style, tables, sequences): + # NB: The generated SQL below is specific to MySQL + # 'TRUNCATE x;', 'TRUNCATE y;', 'TRUNCATE z;'... style SQL statements + # to clear all tables of all data + if tables: + sql = ['SET FOREIGN_KEY_CHECKS = 0;'] + for table in tables: + sql.append('%s %s;' % (style.SQL_KEYWORD('TRUNCATE'), style.SQL_FIELD(self.quote_name(table)))) + sql.append('SET FOREIGN_KEY_CHECKS = 1;') + + # 'ALTER TABLE table AUTO_INCREMENT = 1;'... style SQL statements + # to reset sequence indices + sql.extend(["%s %s %s %s %s;" % \ + (style.SQL_KEYWORD('ALTER'), + style.SQL_KEYWORD('TABLE'), + style.SQL_TABLE(self.quote_name(sequence['table'])), + style.SQL_KEYWORD('AUTO_INCREMENT'), + style.SQL_FIELD('= 1'), + ) for sequence in sequences]) + return sql + else: + return [] + + def value_to_db_datetime(self, value): + # MySQL doesn't support microseconds + if value is None: + return None + return unicode(value.replace(microsecond=0)) + + def value_to_db_time(self, value): + # MySQL doesn't support microseconds + if value is None: + return None + return unicode(value.replace(microsecond=0)) + + def year_lookup_bounds(self, value): + # Again, no microseconds + first = '%s-01-01 00:00:00' + second = '%s-12-31 23:59:59.99' + return [first % value, second % value] + +class DatabaseWrapper(BaseDatabaseWrapper): + + operators = { + 'exact': '= %s', + 'iexact': 'LIKE %s', + 'contains': 'LIKE BINARY %s', + 'icontains': 'LIKE %s', + 'regex': 'REGEXP BINARY %s', + 'iregex': 'REGEXP %s', + 'gt': '> %s', + 'gte': '>= %s', + 'lt': '< %s', + 'lte': '<= %s', + 'startswith': 'LIKE BINARY %s', + 'endswith': 'LIKE BINARY %s', + 'istartswith': 'LIKE %s', + 'iendswith': 'LIKE %s', + } + + def __init__(self, **kwargs): + super(DatabaseWrapper, self).__init__(**kwargs) + self.server_version = None + + self.features = DatabaseFeatures() + self.ops = DatabaseOperations() + self.client = DatabaseClient() + self.creation = DatabaseCreation(self) + self.introspection = DatabaseIntrospection(self) + self.validation = DatabaseValidation() + + def _valid_connection(self): + if self.connection is not None: + try: + self.connection.ping() + return True + except DatabaseError: + self.connection.close() + self.connection = None + return False + + def _cursor(self, settings): + if not self._valid_connection(): + kwargs = { + 'conv': django_conversions, + 'charset': 'utf8', + 'use_unicode': True, + } + if settings.DATABASE_USER: + kwargs['user'] = settings.DATABASE_USER + if settings.DATABASE_NAME: + kwargs['db'] = settings.DATABASE_NAME + if settings.DATABASE_PASSWORD: + kwargs['passwd'] = settings.DATABASE_PASSWORD + if settings.DATABASE_HOST.startswith('/'): + kwargs['unix_socket'] = settings.DATABASE_HOST + elif settings.DATABASE_HOST: + kwargs['host'] = settings.DATABASE_HOST + if settings.DATABASE_PORT: + kwargs['port'] = int(settings.DATABASE_PORT) + kwargs.update(self.options) + self.connection = Database.connect(**kwargs) + cursor = self.connection.cursor() + return cursor + + def _rollback(self): + try: + BaseDatabaseWrapper._rollback(self) + except Database.NotSupportedError: + pass + + def get_server_version(self): + if not self.server_version: + if not self._valid_connection(): + self.cursor() + m = server_version_re.match(self.connection.get_server_info()) + if not m: + raise Exception('Unable to determine MySQL version from version string %r' % self.connection.get_server_info()) + self.server_version = tuple([int(x) for x in m.groups()]) + return self.server_version |