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 tbl_lazy group_by(.data, ..., .add = FALSE, add = NULL, .drop = TRUE)
.data | A lazy data frame backed by a database query. |
---|---|
... | < |
.add | When This argument was previously called |
add | Deprecated. Please use |
.drop | Not supported by this method. |
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()#> <SQL> #> SELECT `g`, COUNT(*) AS `n()` #> FROM `dbplyr_015` #> GROUP BY `g`#> <SQL> #> SELECT `g`, `x`, `x` / SUM(`x`) OVER (PARTITION BY `g`) AS `x2` #> FROM `dbplyr_015`