Question

How is the join done in this scenario?

1) By connecting the common columns
2) By connecting the primary keys
3) By connecting the foreign keys
4) By connecting the unique columns

Answer 1

The join in a database is done by connecting the foreign keys to the primary keys of the related table. The correctness of a table and the grouping of data depend on the specific needs of the application.

Step-by-step explanation:

In this scenario, the join is done by connecting the common columns. When joining tables, the common columns are used as the matching criteria to combine the rows from both tables into a single result set. These common columns could be any overlapping attributes or fields in the two tables.

For example, if we have two tables, Table A and Table B, and both tables have a column called 'ID', we can join the tables using the common column 'ID'. The join operation will match rows from both tables where the 'ID' values are equal, combining them into a result set.

Connecting primary keys, foreign keys, or unique columns are also valid ways to join tables in certain scenarios, but in this specific scenario, the join is done by connecting the common columns.