Database & SQL Basics — Patwari Notes
A basic understanding of databases, DBMS and SQL (Structured Query Language) — a topic asked about directly in actual Patwari PYQs, explained here with examples such as MySQL and Oracle.
- RSCIT-level depth
- 6 min read
What are a Database and a DBMS?
A Database is a collection of data stored in an organized way, which can be easily accessed, managed and updated — for example, a school's record of all students' names, roll numbers and marks. A DBMS (Database Management System) is the software that creates a database and handles adding data to it, searching it and keeping it safe — like a library's digital catalogue system.
When data is kept as tables that are linked to one another, it is called an RDBMS (Relational Database Management System) — this is the most widely used database method today.
SQL — The Language of Databases
SQL (Structured Query Language) is the most popular and standard query language used by relational database management systems (RDBMS). It is used to search for data in a database (SELECT), add new data (INSERT), change data (UPDATE), and remove data (DELETE). In exams, both the full form of SQL and the fact that it is the most popular query language are asked about directly.
Popular DBMS Software
| DBMS | Feature |
|---|---|
| MySQL | Free (open-source), most widely used on websites |
| Oracle | A powerful commercial DBMS used in large organizations/enterprises |
| Microsoft Access | A desktop database tool that comes with MS Office, for small-scale use |
| PostgreSQL | A free, open-source RDBMS with advanced features |
| MongoDB | A NoSQL database — stores data as documents instead of tables |
Memory Trick / Exam Tip
Memory trick: remember SQL as 'Structured Query Language' — a language to 'Query' (ask about/search) data that is 'Structured' (organized) into tables (rows-columns). Keep in mind that names like DML (Data Manipulation Language) or OQL are not synonyms for SQL but separate technical terms — exams place these as confusing options.
Frequently Asked Questions
What is the full form of SQL?+
The full form of SQL is Structured Query Language — it is the most popular language for searching and managing data in a relational database.
What is the difference between a database and a DBMS?+
A database is a collection of data stored in an organized way, whereas a DBMS is the software that creates, manages and provides access to that database.
Name any two popular DBMS software.+
MySQL and Oracle are two of the most popular DBMS software; Microsoft Access, PostgreSQL and MongoDB are also widely used.
What is an RDBMS?+
When data is stored as tables that are related to one another, that system is called an RDBMS (Relational Database Management System).