Question

If x and y are two tbls, which of the following joins return all rows from x where there are matching values in y, and all columns from x and y?

Answer 1

To return all rows from x where there are matching values in y, and all columns from x and y , we use inner_join().

In case of multiple matches between x and y, all combination of the matches are printed.

The syntax use for inner join is :

SELECT ColumnName(s) (separated by ",")

FROM table x

INNER JOIN table y ON  table x.columnName = table y.columnName;

Answer 2

If x and y are two tbls, Mutating joins return all rows from x where there are matching values in y, and all columns from x and y.

The kind used here is inner_join().

It combines variables from two different data.frames.

If there happens to be multiple matches among y and x, all the other combinations of the respective matches get returned.