Nissan Software Engineer Interview Questions and Answers

An index is a data structure that improves the speed of data retrieval operations on a database table.

• Indexes are created on one or more columns of a table.

• They allow for faster searching, sorting, and filtering of data.

• Examples include B-tree, hash, and bitmap indexes.

• Indexes can also have unique constraints to enforce data integrity.

• However, they can also slow down data modification operations like insert, update, an

There are different types of indexes in databases, including clustered, non-clustered, unique, and full-text indexes.

• Clustered index determines the physical order of data in a table based on the indexed column.

• Non-clustered index creates a separate structure that includes the indexed column and a pointer to the actual data.

• Unique index ensures that the indexed column has unique values.

• Full-text index enables searching ...read more

Index is used to improve the performance of database queries by allowing faster data retrieval.

• Index is a data structure that stores a small portion of the table data in an easily searchable format.

• It helps in reducing the number of disk I/O operations required to retrieve data from a table.

• Indexes can be created on one or more columns of a table.

• Examples of indexes include primary key, unique key, clustered index, and

Joins are used to combine data 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 matching rows from the right table

• Right join returns all rows from the right table and matching rows from the left table

• Full outer join returns all rows from both tables

• Cross join returns the Cartesian product of both t