CDC (Change Data Capture) and unidirecional replication options

[JChiappa]

I will need replicate some tables (in uni-direcional mode, only, and refreshing data nightly) from some SQLServer 2000, Oracle 9ir2EE and Oracle 10gr2 EE databases (in diverse servers, some running Windows, some linux, but all of them network-accesible) to a 10gr2 EE db : I tested replication with MVs with a big success, but I´m considering CDC too, but I have some doubts to be smashed from the real experiences from the members :

a. some Oracle source dbs are in noarchive mode : in the "Oracle® Database Data Warehousing Guide 10g Release 2" manual, chapter 16 - Change Data CaptureAsynchronous Distributed HotLog Mode , it says :

"In the asynchronous Distributed HotLog mode, change data is captured from the online redo log file on the source database"

So as I understand the noarchive mode in the source dbs are not a problem, right ? I question it because the entry in http://www.rittmanmead.com/2006/04/1...and-owb-paris/ puts archivemode as a need , togheter with activated global_name parameter, as some metalink notes do, is it right or wrong ?

b. some LONGs and LONG RAWs are present, unfortunately, and can´t be changed right now, and all the docs says that LONGs are not supported in replication of any type : can I create a view "translating" the LONGs to LOBs and use the view as the data source ? If not, some small example of triggers doing it ?

c) speaking in triggers, if I switch to synchronous CDC (the made with triggers one), is possible to refresh only at certain times ? The quoted manual says that sync CDC is in immediate, commit-base only, BUT imho if it maintains a log table (and it does) , maybe could be possible another way of refreshing...

d) any gotchas, recommendations and alike for this scene ?

Regards,

Chiappa

[JChiappa]

I made some testing, and will reply myself :

item a. : another people pointed me to other part of the docs where the need for archive mode are : the reason is, if the capture process can´t cope whith the frequency of alterations, it will use the archived logs.


item b. : no work-arounds for CDC with LONGs, will be needed some manual programing, point taken.

item c : unknow at the moment


Regards,

Chiappa