Major Description
Consider the following dataframes:
"""
left_table:
-----------------------------------------+
| head_id_left | tail_id_left | weight | joining_column |
-----------------------------------------+
| 1 | 2 | 1 | 1~2 |
-----------------------------------------+
right_table:
------------------------------------
| head_id_right | tail_id_right | joining_column |
------------------------------------
------------------------------------
"""
The following code returns an empty dataframe:
"""
joined_table = left_table.join(right_table, "joining_column", "outer")
"""
joined_table has zero rows.
However:
"""
joined_table = left_table.join(right_table, left_table.joining_column == right_table.joining_column, "outer")
"""
returns the correct answer with one row.
