ex_data_table_step.relop_theta_join: Theta join (database implementation).

In WinVector/rqdatatable: 'rquery' for 'data.table'

Theta join (database implementation).

Description

Limited implementation. All terms must be of the form: "(table1.col CMP table2.col) (, (table1.col CMP table2.col) )".

Usage

## S3 method for class 'relop_theta_join'
ex_data_table_step(
  optree,
  ...,
  tables = list(),
  source_usage = NULL,
  source_limit = NULL,
  env = parent.frame()
)

Arguments

optree	relop operations tree.
...	not used, force later arguments to bind by name.
tables	named list map from table names used in nodes to data.tables and data.frames.
source_usage	list mapping source table names to vectors of columns used.
source_limit	if not null limit all table sources to no more than this many rows (used for debugging).
env	environment to work in.

Examples

 d1 <- data.frame(AUC = 0.6, R2 = 0.2)
 d2 <- data.frame(AUC2 = 0.4, R2 = 0.3)

 optree <- theta_join_se(local_td(d1), local_td(d2), "AUC >= AUC2")

 ex_data_table(optree, tables = list(d1 = d1, d2 = d2)) %.>%
   print(.)

WinVector/rqdatatable documentation built on Aug. 22, 2023, 3:25 p.m.