Re: Zope database connectivity
Maciej Wisniowski <[email protected]>
| Newsgroups | gmane.comp.web.zope.database |
|---|---|
| Message-ID | <[email protected]> |
>Not strictly speaking in ZODB: > > The "_v_" use for database connections is dangerous (and if you > want buggy). > > It can lead to nasty, apparently non-deterministic effects. > You may lose your database connection mid transaction > and part of what you think is a transaction (i.e. atomical) can be lost. > > There are too ways to fix this problem: do not use "_v_" attributes > to maintain the database connection or extend the ZODB to > allow more control over the lifetime of "_v_" attributes. > Thanks again for explanations. Seems that I'll change my DA's (DCOracle2 and ZCxOracleDA) to use connection pool like psycopg does. After quick look at their (psycopg) solution I think it is really good and solves (or may solve) few other issues too - like closing all connections with 'Close connection' button (useless with _v_ implementation). Implementing reconnect of broken connection i.e. when database was restarted shouldn't be too difficult too. -- Maciej Wisniowski