TODO.
Joins
Join Algorithms
Join algorithms are the algorithms used to join two tables’ rows on a shared column to produce a resultant table.
There are several join algorithms, but this is a simple join algorithm called the nested loop join:
result_table = {}
for outer_row in outer_table:
for inner_row in inner_table:
if same_join_col_val(inner_row, outer_row):
combined_row = inner_row + outer_row
result_table.upsert(combined_row)