With version 2.7 (and 2.7.1rc1), the following sequence (see attached test): c = cursor.execute(' select k from t where k == ?;', (1,)) conn.commit() r = c.fetchone() Traceback (most recent call last): File "/bugs/sqlite_bug.py", line 22, in <module> c = cursor.execute(' select k from t where k == ?;', (2,)) sqlite3.InterfaceError: Error binding parameter 0 - probably unsupported type. The program works with 2.6.2