dbplyr: group_by.tbl_lazy – R documentation

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group_by.tbl_lazy

Group by one or more variables

Description

This is a method for the dplyr group_by() generic. It is translated to the GROUP BY clause of the SQL query when used with summarise() and to the PARTITION BY clause of window functions when used with mutate().

Usage

## S3 method for class 'tbl_lazy'
group_by(.data, ..., .add = FALSE, add = NULL, .drop = TRUE)

Arguments

`.data`	A lazy data frame backed by a database query.
`...`	<`data-masking`> Variables, or functions of variables. Use `desc()` to sort a variable in descending order.
`.add`	When `FALSE`, the default, `group_by()` will override existing groups. To add to the existing groups, use `.add = TRUE`. This argument was previously called `add`, but that prevented creating a new grouping variable called `add`, and conflicts with our naming conventions.
`add`	Deprecated. Please use `.add` instead.
`.drop`	Not supported by this method.

Examples

library(dplyr, warn.conflicts = FALSE)

db <- memdb_frame(g = c(1, 1, 1, 2, 2), x = c(4, 3, 6, 9, 2))
db %>%
  group_by(g) %>%
  summarise(n()) %>%
  show_query()

db %>%
  group_by(g) %>%
  mutate(x2 = x / sum(x, na.rm = TRUE)) %>%
  show_query()

dbplyr

A 'dplyr' Back End for Databases

v2.1.1

MIT + file LICENSE

Authors

Hadley Wickham [aut, cre], Maximilian Girlich [aut], Edgar Ruiz [aut], RStudio [cph, fnd]

Initial release