How to reuse the same Rows to write the same output twice

Lorenzo5 — Wed, 18 Jan 2017 14:14:48 GMT

Hi,

I'm stuck with a tricky trouble. Try to explain as clear as possible.

tPostgresqlInput --> tMap (joining with other source) --> tAggregateRow --> tPostgresqlOutput

Now, I have also to aggregate rows extracted by the first component (before the tMap) to obtain a sum (that I cannot obtain after the tMap lookup, of course) and put this sum in the same output flow that I'm writing with the Output component:

tPostgresqlInput --> tMap (joining with other source) --> tAggregateRow --\
L tReplicate --> tAggregateRow ----------------------------------------> tJoin --> tPostgresqlOutput

(With the diagram abowe I mean flows split initially and join later, with different elaborations but the same aggregations, with a tJoin component).

Talend does not permit me this solution (I'm not able to re-join the two separate flows later, with a tJoin component)
Why?

The alternat solution, of course, would be extract data twice, with two different tPostgresqlInput (with the same query), managing the two flows in two separate subjob, and writing data with two different Output components (to the same destination), first time in insert, second time in update.
But this solution force me to extract the same amount of data (tPostgresqlInput) twice, and it is bad.

Any suggestion?

Thank you,
Lorenzo

Re: How to reuse the same Rows to write the same output twice

TRF — Wed, 18 Jan 2017 14:29:45 GMT

You may use a tHashOutpout to memorize the SELECT result, the reuse it as many times you need with a tHashInput
Regards,
TRF

topic Re: How to reuse the same Rows to write the same output twice in Talend Studio

How to reuse the same Rows to write the same output twice

Re: How to reuse the same Rows to write the same output twice