join
method. Note, the join's on
method returns a data table because there is no other transform option. There is no need to call a separate table
method to create the table.sales
and product
data tables using the join
method.Id
in data table being joined.join
method to combine the records in two data tables. In SQL terms, this operation uses an inner join. This means the column values for the joined columns need to exist in both data tables for a record to be included in the resulting table.leftJoin
method returns all rows from the left table with the matching rows in the right table. The result is null
on the right side for all columns when there is no match on the joined field.id
3
so the resulting table will have a null value in the comment
column for that row. If the left join was reversed and movies
was joined with movieComments
, movie id
3
would not be included in the resulting table because it does not exist in movieComments
.