Bajaj Allianz Life Insurance Oracle SQL and PLSQL Developer Interview Questions and Answers

Joining tables is done using JOIN keyword. Types of joins include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

• JOIN keyword is used to combine rows from two or more tables based on a related column between them.

• INNER JOIN returns only the matching rows from both tables.

• LEFT JOIN returns all rows from the left table and the matching rows from the right table.

• RIGHT JOIN returns all rows from the right table and the m...read more

Primary key is a column or set of columns that uniquely identifies each row in a table.

• Primary key ensures data integrity by preventing duplicate rows.

• Primary key can be a single column or a combination of columns.

• Primary key is used as a reference in foreign keys of other tables.

• Primary key values cannot be null.

• Primary key values must be unique.