Reference

Join operations

anti_join	Anti join: return rows from x that have no match in y.
full_join	Full (outer) join: return all rows from both x and y.
inner_join	Inner join: return rows present in both x and y.
left_join	Left join: return all rows from x, matching rows from y.
right_join	Right join: equivalent to left_join(y, x, by).
semi_join	Semi join: return rows from x that have matches in y.

Mutate and select

mutate_all	Apply a function to all columns of a DataFrame.
mutate_at	Apply a function to specific columns of a DataFrame.
mutate_if	Apply a function to columns matching a predicate.
select_if	Select columns of a DataFrame that satisfy a predicate.
transmute_at	Apply a function to specific columns, returning only those columns.
transmute_if	Apply a function to columns matching a predicate, returning only those.

Reshape

cast	Cast (pivot) a long-format DataFrame to wide format.
melt	Melt (unpivot) a matrix or DataFrame from wide to long format.

List and nested data

collapse_to_string	Collapse values to a delimited string.
filter_nested	Filter rows of a DataFrame by regex pattern across all columns.
rbind_to_dataframe	Convert a named dictionary of dictionaries to a DataFrame.
split_by_level	Split a DataFrame by the levels of a Categorical column.
unlist2	Unlist a dictionary of DataFrames into a single DataFrame.
unnest2	Explode a list-column into long format.