cdata (version 1.0.7)

map_fields_q: Map field values from one column into new derived columns (query based, takes name of table).

Description

Map field values from one column into new derived columns (query based, takes name of table).

Usage

map_fields_q(dname, cname, mname, my_db, rname)

Arguments

dname

name of table to re-map.

cname

name of column to re-map.

mname

name of table of data describing the mapping (cname column is source, derived columns are destinations).

my_db

database handle.

rname

name of result table.

Value

re-mapped table

Examples

# NOT RUN {
if (requireNamespace("DBI", quietly = TRUE) &&
  requireNamespace("RSQLite", quietly = TRUE)) {
  my_db <- DBI::dbConnect(RSQLite::SQLite(),
                          ":memory:")
  DBI::dbWriteTable(
    my_db,
    'd',
    data.frame(what = c("acc", "loss",
                        "val_acc", "val_loss"),
               score = c(0.8, 1.2,
                         0.7, 1.7),
               stringsAsFactors = FALSE),
    overwrite = TRUE,
    temporary = TRUE)
  DBI::dbWriteTable(
    my_db,
    'm',
    data.frame(what = c("acc", "loss",
                        "val_acc", "val_loss"),
               measure = c("accuracy", "log-loss",
                           "accuracy", "log-loss"),
               dataset = c("train", "train", "validation", "validation"),
               stringsAsFactors = FALSE),
    overwrite = TRUE,
    temporary = TRUE)

  map_fields_q('d', 'what', 'm', my_db, "dm")
  cdata::qlook(my_db, 'dm')
  DBI::dbDisconnect(my_db)
}

# }