rquery: Relational Algebra In R

Kevin Feasel

2017-12-29

R

John Mount announces rquery:

rquery is Win-Vector LLC‘s currently in development big data query tool for R.

rquery supplies set of operators inspired by Edgar F. Codd‘s relational algebra (updated to reflect lessons learned from working with RSQL, and dplyr at big data scale in production).

As an example: rquery operators allow us to write our earlier “treatment and control” example as follows.

dQ <- d %.>% extend_se(., if_else_block( testexpr = "rand()>=0.5", thenexprs = qae( a_1 := 'treatment', a_2 := 'control'), elseexprs = qae( a_1 := 'control', a_2 := 'treatment'))) %.>% select_columns(., c("rowNum", "a_1", "a_2"))

It’s an interesting idea.

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