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Introduction to SQL and Database with example

            Introduction to SQL and Database

What is SQL?

  • SQL is a language used to retrieve and manipulate data in a RDMS.
  • SQL stands for Structured Query Language.

What is a Database?

  • A database is a place to store data.
  • A relational database system (RDBMS) stores data in tables.

Relational Database Tables

  • A relational database stores data in tables. Each table has a number of rows and columns.
  • The table below has 4 rows and 3 columns.


SQL and Relational Databases

  • A relational database contains tables which store data that is related in some way.
  • SQL is the language that allows retrieval and manipulation of table data in a relational database.
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