In "Choosing to store data in SQL vs ZODB" located http://www.zope.org/Members/anthony/sql_vs_ZODB i read : "Will the data be frequently changing? If the data is going to be frequently changing, then it's not a good idea to put it in the ZODB. Every time the data changes, a new record will be appended to the Data.fs file - this could become a problem very quickly." Does that mean that the changes AND the old version of the object are kept in ZODB ? If it's true, is packing a good way to throw away the old versions of the object ? If Not, What are the good ways ? Well i hope that's my last question for today. Thanks Andre
on or about, Wednesday, January 15, 2003, we have reason to believe that aborel wrote something along the lines of :
In "Choosing to store data in SQL vs ZODB" located http://www.zope.org/Members/anthony/sql_vs_ZODB [snip..] Does that mean that the changes AND the old version of the object are kept in ZODB ?
Yes. Every transaction is appended to the data.fs-file.
If it's true, is packing a good way to throw away the old versions of the object ?
Yes. If you have an application that causes your data.fs to grow, you might consider using cron or something similar to pack automatically at regular intervals. -- Geir Bækholt geir@funcom.com Web Application/HCI-designer Product Operations Funcom Oslo
Geir Bækholt a écrit:
on or about, Wednesday, January 15, 2003, we have reason to believe that aborel wrote something along the lines of :
In "Choosing to store data in SQL vs ZODB" located http://www.zope.org/Members/anthony/sql_vs_ZODB
[snip..]
Does that mean that the changes AND the old version of the object are kept in ZODB ?
Yes. Every transaction is appended to the data.fs-file.
If it's true, is packing a good way to throw away the old versions of the object ?
Yes.
If you have an application that causes your data.fs to grow, you might consider using cron or something similar to pack automatically at regular intervals.
Thanks, i read that. ZODB uses transactions so they need to be stored. i'm stupid or i read too many pages on Python/Zope/Plone. Is there a Zope product running on Windows XP emulating to cron on Unix ?
on or about, Wednesday, January 15, 2003, we have reason to believe that D2 wrote something along the lines of :
Is there a Zope product running on Windows XP emulating to cron on Unix ?
The windows scheduler should be able to do something like it :) on win2k it can be found at [Control Panel] >> [Scheduled Tasks] :) -- Geir Bækholt geir@funcom.com Web Application/HCI-designer Product Operations Funcom Oslo
Am Mittwoch, 15.01.03, um 16:04 Uhr (Europe/Rome) schrieb aborel:
In "Choosing to store data in SQL vs ZODB" located http://www.zope.org/Members/anthony/sql_vs_ZODB
i read : "Will the data be frequently changing?
If the data is going to be frequently changing, then it's not a good idea to put it in the ZODB. Every time the data changes, a new record will be appended to the Data.fs file - this could become a problem very quickly."
Does that mean that the changes AND the old version of the object are kept in ZODB ?
yes
If it's true, is packing a good way to throw away the old versions of the object ?
yes
If Not, What are the good ways ?
Well i hope that's my last question for today.
Thanks
Andre
Bernd
That is speed !!! Thanks Bernd Bernd Kulawik a écrit:
Am Mittwoch, 15.01.03, um 16:04 Uhr (Europe/Rome) schrieb aborel:
In "Choosing to store data in SQL vs ZODB" located http://www.zope.org/Members/anthony/sql_vs_ZODB
i read : "Will the data be frequently changing?
If the data is going to be frequently changing, then it's not a good idea to put it in the ZODB. Every time the data changes, a new record will be appended to the Data.fs file - this could become a problem very quickly."
Does that mean that the changes AND the old version of the object are kept in ZODB ?
yes
If it's true, is packing a good way to throw away the old versions of the object ?
yes
If Not, What are the good ways ?
Well i hope that's my last question for today.
Thanks
Andre
Bernd
At 11:04 2003-01-15 -0400, aborel said:
In "Choosing to store data in SQL vs ZODB" located http://www.zope.org/Members/anthony/sql_vs_ZODB
i read : "Will the data be frequently changing?
If the data is going to be frequently changing, then it's not a good idea to put it in the ZODB. Every time the data changes, a new record will be appended to the Data.fs file - this could become a problem very quickly."
Does that mean that the changes AND the old version of the object are kept in ZODB ?
Yes.
If it's true, is packing a good way to throw away the old versions of the object ?
Yes.
If Not, What are the good ways ?
You could also use a non-logging storage or some other more lightweight storage. (The session data manager uses a RAM-based storage, which isn't persistent over reboots, but works well as frequent writes, short time storage.) I also believe a non-logging storage is used for the Wikis on Zope.org. If your going to have really high write frequency SQL probably the most sensible choice. There are some really high-end database manager available for you. A SQL server could also sensible if you want to do queries (as available through SQL (calculations, subqueries and that kind of thing). This will most probably be faster than any special Python/ZCatalog equivalent, at least for substantial amount of data (which RDBMs are designed to handle). ZODB/ZCatalog are not designed to do these things. Hm.. That's a bit more information that you asked for ;-) I think I better stop now ;-) Cheers, Johan Carlsson -- Torped Strategi och Kommunikation AB Johan Carlsson johanc@easypublisher.com Mail: Birkagatan 9 SE-113 36 Stockholm Sweden Visit: Västmannagatan 67, Stockholm, Sweden Phone +46-(0)8-32 31 23 Fax +46-(0)8-32 31 83 Mobil +46-(0)70-558 25 24 http://www.easypublisher.com http://www.torped.se
participants (6)
-
aborel -
Bernd Kulawik -
D2
-
fritz -
Geir B�kholt -
Johan Carlsson [EasyPublisher]