In fact, there's no "join" component yet.
It will be certainly available later.
There is still a way to make a "join" with the tMap, even if this may be a bit difficult to do it without the documentation yet.
The only thing is that the "reference" must have a limited amount of datas. I mean that you can't have for example 1gb of datas in the reference, as all references will be loaded in the memory if you use this way.
Sure, I agree, "join" is a major functionality!
As Nicolas wrote, Talend has not yet a simple mono-join component.
But our tMap component can handle multiple (possibly complex) join at a time.
Here is how to do it (it's much more simple than it appears!):
First, Drag n' drop the following components :
Edit then load (or create) de schema for the tFileInputDelimited.
Then connect your tFileInputDelimited to a tMap.
Then, right-clicking on the tMap, create an new output and connect it to the tFileOutputDelimited.
Then add a new tFileInputDelimited (for example) and place it above the tMap component ; this data source will be taken for the lookup.
Create a connection beetween this new tFileInput and the tMap right clicking on the new tFileInputDelimited and selecting the Row item ; notice than this new link is in dash-point-style and as a "lookup"
Now open the tMap double-clicking on the component.
As you can see the tMap has now 2 tables on the left.
The first one is your main data source. The second one is your lookup data source.
Now all you have to do is to create the joint beetween those tables.
For that, simply drag'n drop your id row of the first table on the id row of the second table.
As yous should see, a new link appears on the left (in yellow).
Now select some rows on the first and on the second table and drag'n drop them on the table on the right.
and......That's all ;-)
As a tips I can explain (on demand!) how you can transform the key to perform more complex lookup.
Full documentation will be available soon... (next week)!
Note1: you can use any input/output component to connect to/from (eg. Delimited, XML, DB...).
Note2: the tMap accept One main data source, as many lookup source as you want and as many output as you want...