ex_data_table_step.relop_select_columns: Implement drop columns.

Description Usage Arguments Examples

View source: R/relop_select_columns.R

Description

data.table based implementation.

Usage

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## S3 method for class 'relop_select_columns'
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

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dL <- data.frame(x = 1, y = 2, z = 3)
rquery_pipeline <- local_td(dL) %.>%
  select_columns(., "y")
dL %.>% rquery_pipeline

rqdatatable documentation built on Jan. 23, 2022, 1:06 a.m.