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SQL

SQL is a language that was specifically invented to manage and maneuver data. It can be classified further into the following types:

  • Data Query Language (DQL) for extracting data. With the syntax like SELECT column1, column2 FROM table WHERE conditions, it can query against the table and extracts data (column1, column2) that satisfies a certain condition.
  • Data Manipulation Language (DML) for manipulating data. It includes statements such as INSERT, UPDATE, and DELETE.
  • Data Control Language (DCL) for controlling data access.

Although we have introduced a number of different languages here, the good thing is that we don't need to learn all of them. In fact, we are not going to query our database using SQL. We will just need to code in Python, and the ORM package will convert our Python code to SQL behind the scenes. It's a whole lot easier to work with databases nowadays.

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