Head Field Solutions Data Scientist 2 Interview Questions and Answers

SQL joins are used to combine rows from two or more tables based on a related column between them.

• Use INNER JOIN to return rows when there is at least one match in both tables.

• Use LEFT JOIN to return all rows from the left table, and the matched rows from the right table.

• Use RIGHT JOIN to return all rows from the right table, and the matched rows from the left table.

• Use FULL JOIN to return rows when there is a match in...read more