54 possible SQL questions that could boost your confidence for your next Database Developer job interview. Well, there are more, but this distilled set of questions covers all SQL functionalities which will enable you to get better prepared to face an interview. You could also enhance your SQL skills with the best SQL Tutorials recommended for you.
Deciding whether to use a SQL-based database or a NoSQL-based database is one of the most important decisions to be made in the planning phase of any project.
Both data management systems have their own application areas, advantages and disadvantages. Before moving on to explain the 8 major differences between SQL and NoSQL database management systems, let us first have a brief introduction of the two contenders.
When developing the schema of a relational database, one of the most important aspect to be taken into account is to ensure that the duplication is minimized. This is done for 2 purposes:
- Reducing the amount of storage needed to store the data.
- Avoiding unnecessary data conflicts that may creep in because of multiple copies of the same data getting stored.
Normalization in DBMS
Database Normalization is a technique that helps in designing the schema of the database in an optimal manner so as to ensure the above points. The core idea of database normalization is to divide the tables into smaller subtables and store pointers to data rather than replicating it. For a better understanding of what we just said, here is a simple Normalization example: