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From: INADA Naoki <songofacandy@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Convert from unsigned long long to PyLong
Date: Mon, 25 Jul 2016 03:59:13 +0900
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Thank you for reporting this issue.

I'll fix it in next release of mysqlclient

(MySQL-python has not been maintained for these years.  Please use mysqlcli=
ent.
It supports Python 3.)

On Fri, Jul 22, 2016 at 3:01 PM, Tian JiaLin <himurakenshin54@gmail.com> wr=
ote:
> HI There,
>
> I'm using MySQLdb as the MySQL client. Recently I got a weird problem of =
this library. After looking into it, I suspect the problem may related to t=
he conversion from unsigned long to PyLongObject.
>
> Here is the detail, If you are familiar with MySQLdb, the following snipp=
et is a way to query the data from MySQL:
>
>
> connection =3D MySQLdb.connect(...)
>
> connection.autocommit(True)
> try:
>     cursor =3D connection.cursor()
>     if not cursor.execute(sql, values) > 0:
>             return None
>     row =3D cursor.fetchone()
> finally:
>     connection.close()
> return row[0]
>
>
> Sometimes the return value of execute method would be 1844674407370955200=
0 even there is no matched data available. I checked the source code of the=
 library, the underlying implementation is https://github.com/farcepest/MyS=
QLdb1/blob/master/_mysql.c#L835,
>
> static PyObject *
> _mysql_ConnectionObject_affected_rows(
>         _mysql_ConnectionObject *self,
>         PyObject *args)
> {
>         if (!PyArg_ParseTuple(args, "")) return NULL;
>         check_connection(self);
>         return PyLong_FromUnsignedLongLong(mysql_affected_rows(&(self->co=
nnection)));
> }
>
> And here is the official doc for mysql_affected_rows http://dev.mysql.com=
/doc/refman/5.7/en/mysql-affected-rows.html.
>
> Let me give a superficial understanding, please correct me if I were wron=
g.
>
> In a 64-bit system, the mysql_affected_rows is supposed to return a numbe=
r of unsigned long, which means the range should be 0 ~ 2^64 (1844674407370=
9551616), How could it be possible the function PyLong_FromUnsignedLongLong=
 return a converted value larger than 2^64, that's what I don't understand.
>
> Does anyone have some ideas of it?
>
>
> The versions of the components I used:
>
> Python: 2.7.6
> MySQL 5.7.11
> MySQLdb 1.2.5
>
>
> Thanks
> --
> https://mail.python.org/mailman/listinfo/python-list



--=20
INADA Naoki  <songofacandy@gmail.com>