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Force computation of a lazy tidyverse object

Source: R/collect_dtx.R
collect_dtx.Rd

When {dplyr} or {tidyr} verbs are applied to a data.table or a database connection, they do not output data frames but objects like dtplyr_step or tbl_sql that are called lazy data frames. The actual process is triggered by using as_dtx(), or more explicitly with dplyr::collect() which coerces the result to a tibble. If you want the default {svBase} data frame object instead, use collect_dtx(), or if you want a specific object, use one of the other variants.

Usage

collect_dtx(x, ...)

collect_dtf(x, ...)

collect_dtt(x, ...)

collect_dtbl(x, ...)

Arguments

x

A data.frame, data.table, tibble or a lazy data frame (dtplyr_step, tbl_sql...).

...

Arguments passed on to methods for dplyr::collect().

Value

A data frame (data.frame, data.table or tibble's tbl_df), the default version for collect_dtx().

Examples

# Assuming the default data frame for svBase is a data.table
mtcars_dtt <- as_dtt(mtcars)
library(dplyr)
library(dtplyr)
# A lazy data frame, not a "real" data frame!
mtcars_dtt |> lazy_dt() |> select(mpg:disp) |> class()
#> [1] "dtplyr_step_subset" "dtplyr_step"       
# A data frame
mtcars |> select(mpg:disp) |> class()
#> [1] "data.frame"
# A data table
mtcars_dtt |> select(mpg:disp) |> class()
#> [1] "data.table" "data.frame"
# A tibble, always!
mtcars_dtt |> lazy_dt() |> select(mpg:disp) |> collect() |> class()
#> [1] "tbl_df"     "tbl"        "data.frame"
# The data frame object you want, default one specified for svBase
mtcars_dtt |> lazy_dt() |> select(mpg:disp) |> collect_dtx() |> class()
#> [1] "data.table" "data.frame"