topic Re: Merging more than one tMap output in Talend Studio

Merging more than one tMap output

Anonymous — Mon, 17 Aug 2015 16:24:55 GMT

Hi. Wonder if someone could help. I have a tMap(tMap1) where the main output goes to tMSSQLOutput. However now I am handling the rejected rows from tMap. So the rejected output from tMap1 goes to tMap2, tMap2 also has an input lookup. The output of tMap1 and tMap2 have same schema. I want to merger the output of tMap1 and tMap2 together (union) and send one union output to tMSSQLOutput. I tried tUnite, but tUnite only accepts one input. tUnite basically works when you are iterating (say a folder full of files) but my requirement here is to perform the union. Any ideas?
Thanks,
Prasad

Re: Merging more than one tMap output

Anonymous — Mon, 17 Aug 2015 19:24:36 GMT

Output to the tHashOutput components from your tMaps and then in another subjob use the tUnite to merge the datasets together.
Once you have separated a single flow into 2 or more flows, you cannot re-merge them in the same subjob. So to get round this, you store the data in memory (for relatively small datasets) and merge them together in another subjob.

Re: Merging more than one tMap output

Anonymous — Tue, 18 Aug 2015 13:18:05 GMT

Thanks. So the output of tMap1 goes to tHashOutput1 and output of tmap2 goes to tHasmOutput2? And in sub job I have two tHashInput components linked to tHashoutput1 and 2 respectively? Not entirely clear on how the subjob should be configured or do I have two sub jobs one for each Hashinput?

Re: Merging more than one tMap output

Anonymous — Tue, 18 Aug 2015 13:45:48 GMT

You would have 2 subjobs; 1 to load the data into the tHashOutput components and 1 to merge the data. You can use a tUnite for this so long as the schemas of both the datasets are the same.

Re: Merging more than one tMap output

Anonymous — Tue, 18 Aug 2015 16:36:02 GMT

Got it. All done. Thanks very much indeed

Re: Merging more than one tMap output

Anonymous — Wed, 19 Aug 2015 04:43:19 GMT

Hi,

Here is a KB article about:TalendHelpCenter:Can I create a Job with multiple paths from a single source to the same target?

Best regards
Sabrina

Re: Merging more than one tMap output

Anonymous — Thu, 11 Jul 2019 21:07:06 GMT

This was the right answer, but I have to mention that in 7.1 and 7.2 versions we have to enable the hash elements under:
Project Settings --> Designer --> Pallete Settings --> Technical

Re: Merging more than one tMap output

Anonymous — Sat, 11 Apr 2020 22:20:29 GMT

For anyone looking for the current link to the support article referenced above, I believe this is it:

https://community.talend.com/t5/Design-and-Development/Can-I-create-a-Job-with-multiple-paths-from-a-single-source-to/ta-p/21653