• Join Wrapper

    Question: Define a function 'jw' which is join wrapper function that can take in any join function (except wj), key column list, left-hand table, right-hand table, and performs the join between them.

    More Information:

    https://code.kx.com/q/basics/joins/

    Example

                                    
                                q)s:([]a:1 2;b:2 3;c:5 7)
q)t:([]a:1 2 3;b:2 3 7;c:10 20 30;d:"ABC")
q)jw[uj;`a`b;s;t]
a b| c  d
---| ----
1 2| 10 A
2 3| 20 B
3 7| 30 C
q)jw[uj;();s;t]
a b c  d
--------
1 2 5
2 3 7
1 2 10 A
2 3 20 B
3 7 30 C
q)jw[lj;`a`b;s;t]
a b c  d
--------
1 2 10 A
2 3 20 B
q)jw[ij;`a`b;s;t]
a b c  d
--------
1 2 10 A
2 3 20 B
q)jw[ej;`a`b;s;t]
a b c  d
--------
1 2 10 A
2 3 20 B

    Solution

    Tags:
    functions tables
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