Fixed #320 -- Changed save() code so that it doesn't rely on cursor.rowcount. MySQLdb sets cursor.rowcount to 0 in an UPDATE statement even if the record already exists. Now save() does a SELECT query to find out whether a record with the primary key already exists.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@507 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Adrian Holovaty 2005-08-15 16:00:28 +00:00
parent b5ed20434e
commit 27986994ee
1 changed files with 14 additions and 6 deletions

View File

@ -728,13 +728,21 @@ def method_save(opts, self):
cursor = db.db.cursor()
# First, try an UPDATE. If that doesn't update anything, do an INSERT.
pk_set = bool(getattr(self, opts.pk.name))
pk_val = getattr(self, opts.pk.name)
pk_set = bool(pk_val)
record_exists = True
if pk_set:
db_values = [f.get_db_prep_save(f.pre_save(getattr(self, f.name), False)) for f in non_pks]
cursor.execute("UPDATE %s SET %s WHERE %s=%%s" % (opts.db_table,
','.join(['%s=%%s' % f.name for f in non_pks]), opts.pk.name),
db_values + [getattr(self, opts.pk.name)])
if not pk_set or cursor.rowcount == 0:
# Determine whether a record with the primary key already exists.
cursor.execute("SELECT 1 FROM %s WHERE %s=%%s LIMIT 1" % (opts.db_table, opts.pk.name), [pk_val])
# If it does already exist, do an UPDATE.
if cursor.rowcount > 0:
db_values = [f.get_db_prep_save(f.pre_save(getattr(self, f.name), False)) for f in non_pks]
cursor.execute("UPDATE %s SET %s WHERE %s=%%s" % (opts.db_table,
','.join(['%s=%%s' % f.name for f in non_pks]), opts.pk.name),
db_values + [pk_val])
else:
record_exists = False
if not pk_set or not record_exists:
field_names = [f.name for f in opts.fields if not isinstance(f, AutoField)]
placeholders = ['%s'] * len(field_names)
db_values = [f.get_db_prep_save(f.pre_save(getattr(self, f.name), True)) for f in opts.fields if not isinstance(f, AutoField)]