x and
y should usually be from the same data source, but if copy is
TRUE, y will automatically be copied to the same source as
x - this may be an expensive operation.inner_join(x, y, by = NULL, copy = FALSE, ...)left_join(x, y, by = NULL, copy = FALSE, ...)
right_join(x, y, by = NULL, copy = FALSE, ...)
full_join(x, y, by = NULL, copy = FALSE, ...)
semi_join(x, y, by = NULL, copy = FALSE, ...)
anti_join(x, y, by = NULL, copy = FALSE, ...)
NULL, the
default, join will do a natural join, using all variables with
common names across the two tables. A message lists the variables so
that you can check they're right.x and y are not from the same data source,
and copy is TRUE, then y will be copied into the
same src as x. This allows you to join tables across srcs, but
it is a potentiallx.