Build a data source description.

Source: R/relop_table_source.R

data.table based implementation. Looks for tables first in tables and then in env. Will accept any data.frame that can be converted to data.table.

# S3 method for relop_table_source
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


dL <- build_frame(
    "x", "y" |
    2L , "b" |
    1L , "a" |
    3L , "c" )
rquery_pipeline <- local_td(dL)
dL %.>% rquery_pipeline

#>   x y
#> 1 2 b
#> 2 1 a
#> 3 3 c