Re: DDL blocking on transaction in other con nection with mvcc transaction model
Fred Toussi via Hsqldb-user <[email protected]> Sat, 24 Jul 2021 10:13:29 +0100
| Newsgroups | gmane.comp.java.hsqldb.user |
|---|---|
| Message-ID | <[email protected]> |
--===============0464450978072507981== Content-Type: multipart/alternative; boundary=f72b285ef5d4426fb57a9d7910ba8f00 --f72b285ef5d4426fb57a9d7910ba8f00 Content-Type: text/plain With MVCC model, you need to use different threads for the two connections. In your usage, the connection that attempts to create a table waits until the connection that has done the SELECT commits. Fred On Fri, Jul 23, 2021, at 11:59, Rob Gansevles wrote: > Hi, > > We are experiencing sometimes a deadlock in our application when creating tables in the in-memory hsql database. > > The connection is created with the hsqldb.tx=mvcc flag. > > When I start a transaction in one connection (autocommit false), select some data, close both the resultset and the statement, and then create a table in another connection without committing the first connection, the application will hang. > > With the default transaction model this works fine. > > Is this expected behaviour, or a bug? > > We could reproduce this with the latest 2.6.1 driver. > > Thanks > Rob > > _______________________________________________ > Hsqldb-user mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/hsqldb-user > --f72b285ef5d4426fb57a9d7910ba8f00 Content-Type: text/html Content-Transfer-Encoding: quoted-printable <!DOCTYPE html><html><head><title></title><style type=3D"text/css">p.Mso= Normal,p.MsoNoSpacing{margin:0}</style></head><body><div style=3D"font-f= amily:Arial;">With MVCC model, you need to use different threads for the= two connections. In your usage, the connection that attempts to create = a table waits until the connection that has done the SELECT commits.&nbs= p; <br></div><div style=3D"font-family:Arial;"><br></div><div style=3D"f= ont-family:Arial;">Fred<br></div><div style=3D"font-family:Arial;"><br><= /div><div>On Fri, Jul 23, 2021, at 11:59, Rob Gansevles wrote:<br></div>= <blockquote type=3D"cite" id=3D"qt" style=3D""><div dir=3D"ltr"><div>Hi,= <br></div><div><br></div><div>We are experiencing sometimes a deadlock i= n our application when creating tables in the in-memory hsql database.<b= r></div><div><br></div><div>The connection is created with the hsqldb.tx= =3Dmvcc flag.<br></div><div><br></div><div>When I start a transaction in= one connection (autocommit false), select some data, close both the res= ultset and the statement, and then create a table in another connection = without committing the first connection, the application will hang.<br><= /div><div><br></div><div>With the default transaction model this works f= ine.<br></div><div><br></div><div>Is this expected behaviour, or a bug?<= br></div><div><br></div><div>We could reproduce this with the latest 2.6= .1 driver.<br></div><div><br></div><div>Thanks<br></div><div>Rob<br></di= v></div><div><br></div><div>____________________________________________= ___<br></div><div>Hsqldb-user mailing list<br></div><div><a href=3D"mail= to:[email protected]">[email protected]<= /a><br></div><div><a href=3D"https://lists.sourceforge.net/lists/listinf= o/hsqldb-user">https://lists.sourceforge.net/lists/listinfo/hsqldb-user<= /a><br></div><div><br></div></blockquote><div style=3D"font-family:Arial= ;"><br></div></body></html> --f72b285ef5d4426fb57a9d7910ba8f00-- --===============0464450978072507981== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline --===============0464450978072507981== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Hsqldb-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/hsqldb-user --===============0464450978072507981==--