Filter table based on other table

thanks austinsense :-)

filter equal is easiest done by merging with JoinKind.Inner as described in these articles:

http://www.thebiccountant.com/2015/08/18/use-timeline-or-slicers-to-filter-your-power-query-import/

http://www.thebiccountant.com/2015/08/21/want-to-filter-a-pivottable-based-on-an-external-range-or-list/

filter < is a bit different: There you have to use parameters. To do so you start filtering your table in the desired way by putting in a hardcoded value. After that you edit the resulting M-code and replace the hardcoded value by the parameter.

The parameter can be retrieved from a table by it's coordinates:

queryname[Columnname]{Rownumber-1}

So say your parameter sits in the first row the expression would be: Tableb[CurrMonth]{0}

Rownumber is zero because M starts to count with 0 (for the 1st row)

So this is how the parametrized filter would look like:

= Table.SelectRows(Source, each [Month] < Tableb[CurrMonth]{0})