And this join happens correctly as well and to the concatenated table1 I get in the field F3 in the row which have value "1" (in this case, frist row of the new made table)
Now, I need additional left join
LOAD * INLINE [
Idea of this one is that in every row where I find value 123 I should add new colum with a new value in a column F3. Technicaly, with inline example I am not showing correctly what is happening and my script is:
LOAD F3 as [F1],
F3 as F1
So, as a bottom line, my first two tables concatenate correctly, and my first join is also correct but the second join simply does not work at all.
The second left join is matching records on the combination of F1 and F3, not just F1. Your left table does not have any records with matching values for both F1 and F3 in the right side table so nothing happens.
Because in your second join F1 and F3 are key fields and your join will look for matching values in both key fields (and since you are not adding additional field values, what information should be added then?).
well, this is closer and I understand the principle but it seems it does not work.
Here is another piece of code which is basically the same as above but loads from data files:
MAPPING LOAD F2,
MAPPING LOAD F1,
ApplyMap('MAP1', F2, ApplyMap('MAP2', F1, null())) as F3
The thing is that I need to match field F2 from my data table with matching row in MAP1 and then add F3 field; if there is no match then I have to try to find if the field F1 has a match in MAP2 and then if there is a match add to field F3 and if there is no match then write down null.
But it does not work.
p.s. please note that in my first code example I have concatenated two tables; in this two examples I have already done that and I am loading single database.