What is SQL?
SQL stands for Structured Query Language, and it is the standard language for working with relational databases. You use it to create tables, add and update data, and most importantly to query data using SELECT statements. Almost every relational database, from MySQL to PostgreSQL to SQL Server, understands SQL.
- SQL is the standard language for storing, querying, and managing data in relational databases.
- Data lives in tables made of rows and columns, linked by keys.
- Common commands are SELECT, INSERT, UPDATE, DELETE, and JOIN.
What you can do with it
- Query data: read rows with SELECT.
- Insert, update, and delete rows to change data.
- Create and change tables and their structure.
- Control who can access what with permissions.
SELECT name, age
FROM users
WHERE age > 18
ORDER BY age DESC;A relational database stores data in tables made of rows and columns, and tables can relate to each other through keys. SQL is how you talk to that data.
Keep the definition short and practical. Say SQL is the standard language to query and manage relational databases, then show a simple SELECT. Interviewers want to see you actually think in tables and rows.
Frequently asked questions
What are the main categories of SQL commands?
DDL defines structure like CREATE, DML changes data like INSERT and UPDATE, DQL queries with SELECT, and DCL controls access with GRANT and REVOKE.
Is SQL case sensitive?
Keywords are not case sensitive, so SELECT and select are the same. Table and column names can be case sensitive depending on the database.
Common follow up questions
Related interview questions
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