rows_delete.dtplyr_step {editbl}

rows_delete implementation for data.table backends.

Description

rows_delete implementation for data.table backends.

Usage

## S3 method for class 'dtplyr_step'
rows_delete(x, y, by = NULL, ..., unmatched, copy = FALSE, in_place = FALSE)

Arguments

x, y

A pair of data frames or data frame extensions (e.g. a tibble). y must have the same columns of x or a subset.

by

An unnamed character vector giving the key columns. The key columns must exist in both x and y. Keys typically uniquely identify each row, but this is only enforced for the key values of y when rows_update(), rows_patch(), or rows_upsert() are used.

By default, we use the first column in y, since the first column is a reasonable place to put an identifier variable.

...

Other parameters passed onto methods.

unmatched

For rows_update(), rows_patch(), and rows_delete(), how should keys in y that are unmatched by the keys in x be handled?

One of:

• "error", the default, will error if there are any keys in y that are unmatched by the keys in x.

• "ignore" will ignore rows in y with keys that are unmatched by the keys in x.

copy

If x and y are not from the same data source, and copy is TRUE, then y will be copied into the same src as x. This allows you to join tables across srcs, but it is a potentially expensive operation so you must opt into it.

in_place

Should x be modified in place? This argument is only relevant for mutable backends (e.g. databases, data.tables).

When TRUE, a modified version of x is returned invisibly; when FALSE, a new object representing the resulting changes is returned.

Value

An object of the same type as x. The order of the rows and columns of x is preserved as much as possible. The output has the following properties:

• rows_update() and rows_patch() preserve the number of rows; rows_insert(), rows_append(), and rows_upsert() return all existing rows and potentially new rows; rows_delete() returns a subset of the rows.

• Columns are not added, removed, or relocated, though the data may be updated.

• Groups are taken from x.

• Data frame attributes are taken from x.

If in_place = TRUE, the result will be returned invisibly.

Author(s)

Jasper Schelfhout