group_by.tbl_lazy function

Group by one or more variables

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().

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