Re: [sqlalchemy] Session remove/close MySQL
Thx all NullPool solve my problem create_engine(cnx_str, poolclass=NullPool) 2014-02-07 19:11 GMT+01:00 Claudio Freire klaussfre...@gmail.com: On Fri, Feb 7, 2014 at 2:35 PM, Michael Bayer mike...@zzzcomputing.com wrote: The connection pool, if in use, will then not actually close the connection if it is to remained pooled, it calls rollback() as part of the pool release mechanism. Recent versions of SQLAlchemy allow this to show up in the engine logs like any other rollback, so you probably wouldn't have noticed. And *this* is what was not happening. Somehow, transactions remained open on the database (I checked). that kind of thing generally happens to people when they aren't cleaning up their sessions, or are using awkward engine/connection patterns. the pool has had a lot of bugs fixed but I haven't seen a bug where the pool isn't emitting the rollback when the connection is marked closed. There was an awkward pattern involved: using the session's connection as returned by Session.connection() manually to issue some textual SQL. Other than that, normal thread-local session stuff. -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.
Re: [sqlalchemy] Session remove/close MySQL
On Fri, Feb 7, 2014 at 9:28 AM, Christian Démolis christiandemo...@gmail.com wrote: Hi all, Actually, i have some problem closing my session... I tried using scopedsession with session.remove I tried using normal session with session.close But in both cases, the Mysql session stay open. Why closing session has no effet on current Mysql connections ? SQLAlchemy maintains a pool of connections to the database. When you start a session, it checks a connection out from the pool, and when you close the session, it returns it to the pool. There are various configuration parameters you can use to control how the pool works. See the docs at http://docs.sqlalchemy.org/en/rel_0_9/core/pooling.html Hope that helps, Simon -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.
Re: [sqlalchemy] Session remove/close MySQL
On Feb 7, 2014, at 11:01 AM, Claudio Freire klaussfre...@gmail.com wrote: I've had similar issues with 0.7.10. SA opens an implicit transaction, incorrect, DBAPI does this, please see: http://www.python.org/dev/peps/pep-0249/#commit there is no “explicit transaction” in DBAPI. The docs have tried very hard to emphasize this as it is misleading to new users, but its outside of SQLAlchemy. and neither Session.remove nor Session.close really roll back the transaction session.rollback() rolls back the transaction. if you don’t call that, session.close() is as though you just closed the connection and did nothing, IMHO as it should be. The connection pool, if in use, will then not actually “close” the connection if it is to remained pooled, it calls rollback() as part of the pool release mechanism. Recent versions of SQLAlchemy allow this to show up in the engine logs like any other rollback, so you probably wouldn’t have noticed. (even though they should, I've had lots of experimental evidence that it does not always do it). So, what I suggest, is issuing a session.commit() or session.rollback() (according to your transactional needs) before the session.close/remove -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out. signature.asc Description: Message signed with OpenPGP using GPGMail
Re: [sqlalchemy] Session remove/close MySQL
I knew I should've been more explicit On Fri, Feb 7, 2014 at 1:07 PM, Michael Bayer mike...@zzzcomputing.com wrote: On Feb 7, 2014, at 11:01 AM, Claudio Freire klaussfre...@gmail.com wrote: I've had similar issues with 0.7.10. SA opens an implicit transaction, incorrect, DBAPI does this, please see: http://www.python.org/dev/peps/pep-0249/#commit Ok, yeah. The point is, it's open. and neither Session.remove nor Session.close really roll back the transaction No, but the connection pool should. (reset_on_return, which I have enabled) The connection pool, if in use, will then not actually close the connection if it is to remained pooled, it calls rollback() as part of the pool release mechanism. Recent versions of SQLAlchemy allow this to show up in the engine logs like any other rollback, so you probably wouldn't have noticed. And *this* is what was not happening. Somehow, transactions remained open on the database (I checked). -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.
Re: [sqlalchemy] Session remove/close MySQL
On Fri, Feb 7, 2014 at 2:35 PM, Michael Bayer mike...@zzzcomputing.com wrote: The connection pool, if in use, will then not actually close the connection if it is to remained pooled, it calls rollback() as part of the pool release mechanism. Recent versions of SQLAlchemy allow this to show up in the engine logs like any other rollback, so you probably wouldn't have noticed. And *this* is what was not happening. Somehow, transactions remained open on the database (I checked). that kind of thing generally happens to people when they aren't cleaning up their sessions, or are using awkward engine/connection patterns. the pool has had a lot of bugs fixed but I haven't seen a bug where the pool isn't emitting the rollback when the connection is marked closed. There was an awkward pattern involved: using the session's connection as returned by Session.connection() manually to issue some textual SQL. Other than that, normal thread-local session stuff. -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.
Re: [sqlalchemy] Session remove/close MySQL
On Feb 7, 2014, at 11:16 AM, Claudio Freire klaussfre...@gmail.com wrote: and neither Session.remove nor Session.close really roll back the transaction No, but the connection pool should. (reset_on_return, which I have enabled) reset_on_return is on by default. the pool has always emitted a rollback, the reset_on_return feature was added for some folks who either wanted to do nothing for MySQL/MyISAM, or wanted it to do a commit() on SQL Server. The connection pool, if in use, will then not actually close the connection if it is to remained pooled, it calls rollback() as part of the pool release mechanism. Recent versions of SQLAlchemy allow this to show up in the engine logs like any other rollback, so you probably wouldn't have noticed. And *this* is what was not happening. Somehow, transactions remained open on the database (I checked). that kind of thing generally happens to people when they aren’t cleaning up their sessions, or are using awkward engine/connection patterns. the pool has had a lot of bugs fixed but I haven’t seen a bug where the pool isn’t emitting the rollback when the connection is marked closed. signature.asc Description: Message signed with OpenPGP using GPGMail
Re: [sqlalchemy] Session remove/close MySQL
On Fri, Feb 7, 2014 at 11:51 AM, Simon King si...@simonking.org.uk wrote: On Fri, Feb 7, 2014 at 9:28 AM, Christian Démolis christiandemo...@gmail.com wrote: Hi all, Actually, i have some problem closing my session... I tried using scopedsession with session.remove I tried using normal session with session.close But in both cases, the Mysql session stay open. Why closing session has no effet on current Mysql connections ? SQLAlchemy maintains a pool of connections to the database. When you start a session, it checks a connection out from the pool, and when you close the session, it returns it to the pool. There are various configuration parameters you can use to control how the pool works. See the docs at http://docs.sqlalchemy.org/en/rel_0_9/core/pooling.html I've had similar issues with 0.7.10. SA opens an implicit transaction, and neither Session.remove nor Session.close really roll back the transaction (even though they should, I've had lots of experimental evidence that it does not always do it). So, what I suggest, is issuing a session.commit() or session.rollback() (according to your transactional needs) before the session.close/remove -- You received this message because you are subscribed to the Google Groups sqlalchemy group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.
