Commit 879b245b authored by Claude Paroz's avatar Claude Paroz
Browse files

Fixed #5725 -- Fixed varchar column size introspection for MySQL 

Thanks ferdonline for the initial patch and Karen Tracey for the
related post on django-users.
parent fb3d916c

django/db/backends/mysql/introspection.py

+13 −2
Original line number Diff line number Diff line
@@ -36,9 +36,20 @@ class DatabaseIntrospection(BaseDatabaseIntrospection): 
        return [row[0] for row in cursor.fetchall()]



    def get_table_description(self, cursor, table_name):

        "Returns a description of the table, with the DB-API cursor.description interface."

        """

        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())



        cursor.execute("SELECT * FROM %s LIMIT 1" % self.connection.ops.quote_name(table_name))

        return cursor.description

        return [line[:3] + (length_map.get(line[0], line[3]),) + line[4:]

            for line in cursor.description]



    def _name_to_index(self, cursor, table_name):

        """

tests/regressiontests/introspection/tests.py

+5 −0
Original line number Diff line number Diff line
@@ -89,6 +89,11 @@ class IntrospectionTests(six.with_metaclass(IgnoreNotimplementedError, TestCase) 
            [datatype(r[1], r) for r in desc],

            ['IntegerField', 'CharField', 'CharField', 'CharField', 'BigIntegerField']

        )

        # Check also length of CharFields

        self.assertEqual(

            [r[3] for r in desc if datatype(r[1], r) == 'CharField'],

            [30, 30, 75]

        )



    # Oracle forces null=True under the hood in some cases (see

    # https://docs.djangoproject.com/en/dev/ref/databases/#null-and-empty-strings)