AW: Replication Questions

"Auer, Wolfgang" <[email protected]> Fri, 3 Aug 2007 15:19:50 +0200
Newsgroups gmane.comp.db.maxdb
Message-ID <[email protected]>
Hello Linos,

> 1) when i have to do any structure change (add a column with alter =
table
> for example), it is replicated? or have i to do with replication units
> deactivated and make the structure change in all the clients?

=3D> Structure changes are not replicated. You have to deactivate the =
units and make the structure change in all the clients.

2) If i deactivate the units and later activate them the changes made in
this time are lost? (i refer to all the changes, client and master in a
IN/OUT, if i only have out i know i can "send content to client")

=3D> Yes. You have to do your changes while the application is not =
running. But if you change the application tables, shouldn't the =
application be stopped anyway?

3) I would like to use sequence numbers in the structure (i have the
possibility to use natural keys but any times with multiple columns, not
too much practical), i have tried but when i create the sequence in the
master it is not replicated in the client so i can not use the sequence
in inserts into the client, can i use sequence numbers? what if about
collision, the numbers that in my design can have a collision are
meaningless because i haver other unique columns so i have no problem in
automatically change them in the two databases if i have collision but i
don't  know if i can do it an how.

=3D> Sequences are not replicated. Only the numeric values generated by =
them in a table. So collision can occur for these values.=20
   You should combine the sequence values with some kind of database =
identifier.
   You have to define the sequence on every client.

4) i have not tried yet with triggers, but without foreign keys i am
planning use extensive use of triggers to save the integrity, if i use
exactly the same name scheme, are they replicated? if not, if i add the
triggers with the same name in all clients and the master, would they be
used in propagation?

=3D> The replication triggers of the Synchronization Manager are always =
executed after a "normal" MaxDB trigger.
   The definition of a "normal" MaxDB triggers is not replicated. If a =
trigger changes data in a table this data will be replicated.
=20
Regards
   Wolfgang

Wolfgang Auer=20
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