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lazyfox
2012-07-30, 04:17
Quick search for replication showed hits more in Cloud/backup area.
Has Lianja SQL server support for replication between a central server and local DB tables wired in ?
scenario: part time offline road warrior with installed apps needing to synch with central server again when online.

Or is there replication support only between server instances ?
Then perhaps a very low price installable server only for 1 to 3 connections might be interesting.

regards

thomas

lianjasupport
2012-07-30, 05:57
The replication mentioned is real-time replication on the backend server. This can be configured master-slave or master-many with geo replication. This is Linux backend servers only as windows does not have the needed functionality.

The mobile edition will support offline data synchronization to the master data server which in turn can be replicated as stated above.

It may be also possible to sync backend data on a non real time basis using Dropbox and/or sky drive for less critical data.

lazyfox
2012-07-31, 06:03
thx for the detailed answer. Currently not clear in my mind:


The mobile edition will support offline data synchronization to the master data server which in turn can be replicated as stated above.


Does this imply functionality ONLY found in mobile apps as in [iOS, android] but not in apps deployed to a more common laptop running [win,osx,linux] ?

tia

thomas

lianjasupport
2012-07-31, 07:16
Are you referring to syncing of data or publishing of Apps?

lazyfox
2012-07-31, 10:01
Synching of data - road warrior insurance salesman for instance.

barrymavin
2012-07-31, 10:33
So just out of curiosity how do you currently do this?

lazyfox
2012-08-02, 11:51
lots of code home grown by the fact the system was developed turn of the century,
had to work with fox and DB2 data backends as server repository.
Due to DB2 strictly SQL implementation.
Sometimes biz logic interwoven, large parts table driven -
works now but is neither beautiful nor performant, even if the
crew it was sourced out to was one of the better ones back then.

lianjasupport
2012-08-02, 11:58
Maybe that's something we can do when we do mobile. Back port it into desktop clients.

lazyfox
2012-08-03, 03:39
I think that is the way to approach it - in the increasingly connected world seamless caching/replication of lookup data
provides still constand benefit to installable apps. Local data is the reason for staying with vfp so long and looking at Lianja.
But things like automatic synch/replication are needed in todays world, or pure web apps will edge out installable apps
in biz environments IMO.

IMO solid support for something similar to RowVersion() on SQL Server is the key -
implementing a rowversion, albeit for each table based on the "bigint" money data type
was one of the keys making our replication attempt workable with vfp file data storage.

regards

thomas

lianjasupport
2012-08-03, 10:14
There is a hidden system column that is unique it is called SYNCNUM.

Also the Lianja database engine supports database timelines. With SET TIMELINE ON all changes are recorded in system!systimeline and can be queried. The changes are stored as sparse XML so in fact implementing offline data syncing is relatively straightforward.

We are intending to provide this functionality in the Mobile edition.

HankFay
2012-08-03, 11:34
There is a hidden system column that is unique it is called SYNCNUM.

Also the Lianja database engine supports database timelines. With SET TIMELINE ON all changes are recorded in system!systimeline and can be queried. The changes are stored as sparse XML so in fact implementing offline data syncing is relatively straightforward.

We are intending to provide this functionality in the Mobile edition.

w00t (whatever that means :)