Added AutoField introspection for MySQL (11662022) · Commits · Dom Sekotill / django

django/db/backends/mysql/base.py

+1 −0

Original line number	Diff line number	Diff line
		@@ -173,6 +173,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
		supports_binary_field = six.PY2
		supports_regex_backreferencing = False
		supports_date_lookup_using_string = False
		can_introspect_autofield = True
		can_introspect_binary_field = False
		can_introspect_small_integer_field = True
		supports_timezones = False

django/db/backends/mysql/introspection.py

+31 −18

Original line number	Diff line number	Diff line
		from collections import namedtuple
		import re
		from .base import FIELD_TYPE
		from django.utils.datastructures import OrderedSet
		from django.db.backends import BaseDatabaseIntrospection, FieldInfo, TableInfo
		from django.utils.encoding import force_text

		FieldInfo = namedtuple('FieldInfo', FieldInfo._fields + ('extra',))

		foreign_key_re = re.compile(r"\sCONSTRAINT `[^`]` FOREIGN KEY \(`([^`])`\) REFERENCES `([^`])` \(`([^`])`\)")

		@@ -32,6 +34,12 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
		FIELD_TYPE.VAR_STRING: 'CharField',
		}

		def get_field_type(self, data_type, description):
		field_type = super(DatabaseIntrospection, self).get_field_type(data_type, description)
		if field_type == 'IntegerField' and 'auto_increment' in description.extra:
		return 'AutoField'
		return field_type

		def get_table_list(self, cursor):
		"""
		Returns a list of table and view names in the current database.
		@@ -44,28 +52,33 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
		"""
		Returns a description of the table, with the DB-API cursor.description interface."
		"""
		# varchar length returned by cursor.description is an internal length,
		# not visible length (#5725), use information_schema database to fix this
		cursor.execute("""
		SELECT column_name, character_maximum_length FROM information_schema.columns
		WHERE table_name = %s AND table_schema = DATABASE()
		AND character_maximum_length IS NOT NULL""", [table_name])
		length_map = dict(cursor.fetchall())

		# Also getting precision and scale from information_schema (see #5014)
		# information_schema database gives more accurate results for some figures:
		# - varchar length returned by cursor.description is an internal length,
		# not visible length (#5725)
		# - precision and scale (for decimal fields) (#5014)
		# - auto_increment is not available in cursor.description
		InfoLine = namedtuple('InfoLine', 'col_name data_type max_len num_prec num_scale extra')
		cursor.execute("""
		SELECT column_name, numeric_precision, numeric_scale FROM information_schema.columns
		WHERE table_name = %s AND table_schema = DATABASE()
		AND data_type='decimal'""", [table_name])
		numeric_map = dict((line[0], tuple(int(n) for n in line[1:])) for line in cursor.fetchall())
		SELECT column_name, data_type, character_maximum_length, numeric_precision, numeric_scale, extra
		FROM information_schema.columns
		WHERE table_name = %s AND table_schema = DATABASE()""", [table_name])
		field_info = dict((line[0], InfoLine(*line)) for line in cursor.fetchall())

		cursor.execute("SELECT * FROM %s LIMIT 1" % self.connection.ops.quote_name(table_name))
		return [FieldInfo(*((force_text(line[0]),)
		to_int = lambda i: int(i) if i is not None else i
		fields = []
		for line in cursor.description:
		col_name = force_text(line[0])
		fields.append(
		FieldInfo(*((col_name,)
		+ line[1:3]
		+ (length_map.get(line[0], line[3]),)
		+ numeric_map.get(line[0], line[4:6])
		+ (line[6],)))
		for line in cursor.description]
		+ (to_int(field_info[col_name].max_len) or line[3],
		to_int(field_info[col_name].num_prec) or line[4],
		to_int(field_info[col_name].num_scale) or line[5])
		+ (line[6],)
		+ (field_info[col_name].extra,)))
		)
		return fields

		def _name_to_index(self, cursor, table_name):
		"""