ODI V.11 IKM Oracle Incremental KM is giving a performance bottle neck.

Question

Hi All,
Well I am experimenting with different IKM's for Incrementally loading Target Table.
When i am using V.11 IKM Oracle Incremental update KM, Insert Flow into I$ table step is taking longer time than usual.
And when i do the same process using V.10 IKM Oracle Incremental update, this step Insert Flow into I$ table is finishing in no time.
Hard to believe this....
V.11 KM's should be faster than V.10 KM's right......
Is there any thing in V.11 KM's creating this issue????
Any help appreciated.
Thank you,
Mike.

Answer 1

I think the theory process changed to 'only bring things to the staging / collection layer that is not already in the target'. In some cases this makes sense.
It doesnt help on some of our interfaces so I've created a new option , true / false called 'USE_MINUS' then the minus clause on the IKM to this :
<% if ("1".equals(snpRef.getOption("USE_MINUS"))) { %>
     /* Minus set operator enabled in interface flow control options.*/     
minus
     select
     <%=odiRef.getColList("","[COL_NAME]", ",\n\t", "", "(((INS OR UPD) AND NOT TRG)AND REW)")%>
     ,'I'     IND_UPDATE
from     <%=odiRef.getTable("L", "TARG_NAME", "A")%>
<% } else { %>
     /* Minus set operator disabled in interface flow control options*/
<% } %>
This allows you to turn on / off on a per interface basis, just set the default to off, or delete the entire Minus part if you really dont want it (without any control to re-introduce it)
I wouldnt assume anything is supposed to be quicker from 10g to 11g, they are only code generators, how does Oracle know if it suits every customer implementation? Maybe the Merge from staging to the target is heavier than the Minus in some cases hence the behaviour not to bring anything in you already have.
Anyway hope the above helps.
Rgrds
Alastair