Top SQL Concept Difference Questions Ask In the Interview.

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Let's try to understand essential SQL concepts frequently asked in an interview.

Table of content:

• SQL and MYSQL
• Where VS having
• Union VS Union all
• In VS Exist
• Group by VS Order by
• Join VS Subquery
• Join VS Union
• Primary key Vs Foreign key

1. Difference between SQL and MYSQL.

• SQl is a structured query language whereas MySQL is a relational database that uses SQL to query a database.
• You can use SQL to access, manipulate and update data in a database whereas MySQL is a database that stores data in a database.

2. Difference between Primary and Foreign key.

• A primary key is a unique identifier for a record in a database table, while a foreign key is a reference to the primary key of another table, used to establish a relationship between the two tables.
• The primary key ensures that each record in a table…