John Mount has a new introduction to rquery:
rqueryis a data wrangling system designed to express complex data manipulation as a series of simple data transforms. This is in the spirit ofR’sbase::transform(), ordplyr’sdplyr::mutate()and uses a pipe in the style popularized inRwithmagrittr. The operators themselves follow the selections in Codd’s relational algebra, with the addition of the traditionalSQL“window functions.” More on the background and context ofrquerycan be found here.The
R/rqueryversion of this introduction is here, and thePython/data_algebraversion of this introduction is here.
Check it out.