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Optimizing database queries

This task is particularly important, because when I am using the app, the loading times are incredibly long(like in this post). And the more records I add to the database (I add them daily) - the worse the situation will get.

Some possible solutions to try out:

1 Caching

Consider using Django Middleware like django.middleware.cache.CacheMiddleware to cache views and reduce database hits.

It is surprisingly simple to implement, just add 'django.middleware.cache.CacheMiddleware' after 'django.contrib.auth.middleware.AuthenticationMiddleware', in settings.py and you will already notice the caching behavior.

First page load might take 300ms, but the second time you will load the same page, it will take 0.00ms.

Kind of amazing, BUT I think it only works if the data HAS NOT CHANGED since the last cache. If it has changed - you will have to refetch the whole data and that again will take 300ms.

When I have constantly changing data tables, this will not work for me.

I am sure there are ways to optimize caching to suite my needs better, but this time I just don't feel that this is the solution I should go with.

2 Others

  • Use Select Related or Prefetch Related: If your models have ForeignKey or ManyToMany relationships, using select_related or prefetch_related can help reduce the number of database queries when fetching related objects.
  • Limit Fields: When querying objects, only select the fields you actually need. This can reduce the amount of data retrieved from the database.
  • Indexes: Ensure that your database tables have appropriate indexes on columns that are frequently used for filtering or searching.
  • Caching: Implement caching for data that doesn't change frequently. This can significantly reduce database queries for repetitive requests.
  • Database Optimization: Depending on your database system, there might be database-specific optimizations you can apply.
  • Query Optimization: Review your database queries and optimize them for efficiency. Tools like Django Debug Toolbar can help identify inefficient queries.
  • Remember that the number of queries can also depend on the specific data and relationships in your database, so it's essential to analyze and optimize your database queries based on your application's requirements and usage patterns.