Within transaction, the error disappeared

[nexttonever]

code like this:
db = ...
with db.transaction() as tx:
tx.query(...) # raise an sql error

but the error raised by tx.query disappears.
I found the code:
def transaction(self):
"""A context manager for executing a transaction on this Database."""

    conn = self.get_connection()
    tx = conn.transaction()
    try:
        yield conn
        tx.commit()
    except:
        tx.rollback()
        raise   # This may be the solution
    finally:
        conn.close()

[kennethreitz]

Ask yourself this —