hooks.py 文件源码

def CheckCollationIsUsed(self):
        if sqlite.version_info < (3, 2, 1):  # old SQLite versions crash on this test
            return
        def mycoll(x, y):
            # reverse order
            return -cmp(x, y)

        con = sqlite.connect(":memory:")
        con.create_collation("mycoll", mycoll)
        sql = """
            select x from (
            select 'a' as x
            union
            select 'b' as x
            union
            select 'c' as x
            ) order by x collate mycoll
            """
        result = con.execute(sql).fetchall()
        if result[0][0] != "c" or result[1][0] != "b" or result[2][0] != "a":
            self.fail("the expected order was not returned")

        con.create_collation("mycoll", None)
        try:
            result = con.execute(sql).fetchall()
            self.fail("should have raised an OperationalError")
        except sqlite.OperationalError, e:
            self.assertEqual(e.args[0].lower(), "no such collation sequence: mycoll")