[Django]-How to improve 2 million data query speed in Django RESTful APIs

Some pointers about optimisation for the Django ORM with Postgres:

• Use db_index=True on fields that will be search upon often and have some degree of repetition between entries, like “title”.
• Use values() and values_list() to select only the columns you want from a QuerySet.
• If you’re doing full text search in any of those columns (like a contains query), bear in mind that Django has support for full text search directly on a Postgres database.
• Use print queryset.query to check what kind of SQL query is going into your database and if it can be improved upon.
• Many Postgres optimisation techniques rely in custom SQL queries that can be made in Django by using RawSQL expressions.
• Remember that there are many, many ways to search for data in a database, be it relational or not-relational in nature. In your case, MongoDB is not “faster” than Postgres, it’s just doing a better job at querying what you really want.