Interview Questions on DBMS

DML stands for Data Manipulation Statements. They update data values in table. Below are the most important DDL statements:- SELECT – gets data from a database table UPDATE – updates data in a table DELETE – deletes data from a database table INSERT INTO – inserts new data into a database table DDL stands for … Read more

If we want relational system in conjunction with time we use sixth normal form. At this moment SQL Server does not supports it directly. Yes, I’m familiar with the concept of sixth normal form (6NF) in database management systems (DBMS). It’s an advanced level of normalization in which every non-trivial join dependency in the table … Read more

In fourth normal form it should not contain two or more independent multi-v about an entity and it should satisfy “Third Normal form”. Fifth normal form deals with reconstructing information from smaller pieces of information. These smaller pieces of information can be maintained with less redundancy. Sure, I’d be happy to explain Fourth Normal Form … Read more

Denormalization is the process of putting one fact in numerous places (its vice-versa of normalization).Only one valid reason exists for denormalizing a relational design – to enhance performance.The sacrifice to performance is that you increase redundancy in database. Denormalization in database management refers to the process of intentionally introducing redundancy into a database design, usually … Read more

There is set of rules that have been established to aid in the design of tables that are meant to be connected through relationships. This set of rules is known as Normalization. Benefits of normalizing your database include: Avoiding repetitive entries Reducing required storage space Preventing the need to restructure existing tables to accommodate new … Read more