I've seen how to use tMap in TOS to map different fields in a SQL-like JOIN. How do I aggregate b开发者_开发百科ased on certain fields?
If I have two tables:
[ A, B, C, D ]
and that are tMap'ped to [ B, C, F, G ]
[ B, E, F, G]
how can I aggregate the results to that instead of the many entries of the non-unique B I can see something like:
[ B, count(B), avg(C), avg(F), avg(G) ]
Thanks!
You certainly can. Use the tAggregate component to do that. You can group by column B and then compute all of the different aggregations, like count, sum, and average in the other columns.
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