topic Re: tMap in Java Unique, First, ... Match in Talend Studio

tMap in Java Unique, First, ... Match

Anonymous — Sat, 16 Nov 2024 13:59:40 GMT

Hi,
Thanks for all your previous answers. Could someone explain exactly how does the options Unique/First/Last/All matches work? In fact my question is more about "unique", in what is it different from "First"?

Re: tMap in Java Unique, First, ... Match

amaumont — Wed, 15 Apr 2009 11:04:59 GMT

"Unique" and "Last match" have same behavior and will be merged as only "Unique match" into the next release 3.1.
"Unique" or "Last match" will match with the last key into the lookup, then if you have several rows with the same key, this will the last will match.
Contrary to the "First match" which will match with the first loaded row into the lookup if several rows have same key.

Re: tMap in Java Unique, First, ... Match

Anonymous — Wed, 15 Apr 2009 11:15:36 GMT

Hello

Thanks for all your previous answers.

If the answers solve your question, please say a word in each topic to thank other users/developers, so we know you have fit your questions.

what is it different from "First"?

I show a use case to explain your question,eg:
main:
id;name
1;shong
2;plegall
lookup:
id;age
1;11
1;12
1;13
2;21
3;31
Do a inner join with id key and output id,age column.
"Unique" and "Last match" have same behavior, get:
1;13
first match, get:
1;11
all match, get:
1;11
1;12
1;13
Best regards

shong

Re: tMap in Java Unique, First, ... Match

Anonymous — Thu, 16 Apr 2009 08:50:59 GMT

hi,

If the answers solve your question, please say a word in each topic to thank other users/developers,...

just a little suggestion about that ...
it 'll be great to add a "resolved" status to this forum for "complete answered topics"
(seems that plegall have a look for that on fluxbb forum)
and thanks to all on this forum!

Re: tMap in Java Unique, First, ... Match

Anonymous — Tue, 15 May 2012 14:26:57 GMT

Hi shong,
Thanks for explain with very good example.
Thank you,
Nitin

Re: tMap in Java Unique, First, ... Match

jkrfs — Thu, 23 Aug 2012 15:48:38 GMT

Shong,
How can you get this to work if you have the data reverse? Meaning your main is id/age and the lookup is id/name. It seems that unique/first match does not work in this way.
Thanks