Filtering joins filter rows from
x based on the presence or absence
of matches in
semi_join()return all rows from
xwith a match in
anti_join()return all rows from
xwithout a match in
- x, y
A pair of data frames, data frame extensions (e.g. a tibble), or lazy data frames (e.g. from dbplyr or dtplyr). See Methods, below, for more details.
A join specification created with
join_by(), or a character vector of variables to join by.
NULL, the default,
*_join()will perform a natural join, using all variables in common across
y. A message lists the variables so that you can check they're correct; suppress the message by supplying
To join on different variables between
y, use a
join_by()specification. For example,
join_by(a == b)will match
To join by multiple variables, use a
join_by()specification with multiple expressions. For example,
join_by(a == b, c == d)will match
y$d. If the column names are the same between
y, you can shorten this by listing only the variable names, like
For simple equality joins, you can alternatively specify a character vector of variable names to join by. For example,
by = c("a", "b")joins
y$b. If variable names differ between
y, use a named character vector like
by = c("x_a" = "y_a", "x_b" = "y_b").
To perform a cross-join, generating all combinations of
yare not from the same data source, and
ywill 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.
Other parameters passed onto methods.
An object of the same type as
x. The output has the following properties:
Rows are a subset of the input, but appear in the same order.
Columns are not modified.
Data frame attributes are preserved.
Groups are taken from
x. The number of groups may be reduced.
These function are generics, which means that packages can provide implementations (methods) for other classes. See the documentation of individual methods for extra arguments and differences in behaviour.
Methods available in currently loaded packages:
# "Filtering" joins keep cases from the LHS band_members %>% semi_join(band_instruments) #> Joining with `by = join_by(name)` #> # A tibble: 2 × 2 #> name band #> <chr> <chr> #> 1 John Beatles #> 2 Paul Beatles band_members %>% anti_join(band_instruments) #> Joining with `by = join_by(name)` #> # A tibble: 1 × 2 #> name band #> <chr> <chr> #> 1 Mick Stones # To suppress the message about joining variables, supply `by` band_members %>% semi_join(band_instruments, by = join_by(name)) #> # A tibble: 2 × 2 #> name band #> <chr> <chr> #> 1 John Beatles #> 2 Paul Beatles # This is good practice in production code