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 Developer=20 MaxDB&liveCache=20 SAP AG=20 mailto:[email protected]=20 http://www.sap.com =20 Sitz der Gesellschaft/Registered Office: Walldorf, Germany=20 Vorstand/SAP Executive Board: Henning Kagermann (Sprecher/CEO), L=E9o = Apotheker (stellvertretender Sprecher/Deputy CEO), Werner Brandt, Claus = Heinrich, Gerhard Oswald, Peter Zencke =20 Vorsitzender des Aufsichtsrats/Chairperson of the SAP Supervisory Board: = Hasso Plattner=20 Registergericht/Commercial Register Mannheim No HRB 350269=20 =20 Diese E-Mail kann Betriebs- oder Gesch=E4ftsgeheimnisse oder sonstige = vertrauliche Informationen enthalten. Sollten Sie diese E-Mail = irrt=FCmlich erhalten haben, ist Ihnen eine Kenntnisnahme des Inhalts, = eine Vervielf=E4ltigung oder Weitergabe der E-Mail ausdr=FCcklich = untersagt. =20 Bitte benachrichtigen Sie uns und vernichten Sie die empfangene E-Mail. = Vielen Dank.=20 =20 This e-mail may contain trade secrets or privileged, undisclosed, or = otherwise confidential information. If you have received this e-mail in = error, you are hereby notified that any review, copying, or distribution = of it is strictly prohibited. Please inform us immediately and destroy = the original transmittal. Thank you for your cooperation. -- MaxDB Discussion Mailing List For list archives: http://lists.mysql.com/maxdb To unsubscribe: http://lists.mysql.com/[email protected]