Understand Group by in Django with SQL
Understand GROUP BY in Django ORM by comparing QuerySets and SQL side by side. If SQL is where you are most comfortable, this is the Django GROUP BY tutorial for you.
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12 Common Mistakes and Missed Optimization Opportunities in SQL
SQL is used by analysts, data scientists, product managers, designers and many others. These professionals have access to databases, but they don't always have the intuition and understanding to write efficient queries. In an effort to make my team write better SQL, I went over reports written by non-developers and code reviews, and gathered common mistakes and missed optimization opportunities in SQL.
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- ORM, SQL, PostgreSQL
Preventing SQL Injection Attacks With Python
SQL injection attacks are constantly ranked among the most common attacks against systems. While binding values is very common, I often find my self needing to being table and column names as well. This article will walk you through everything you need to know about SQL injections in Python.
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How "Export to Excel" Almost Killed Our System
Inspired by an actual incident we had in one of our systems caused by an "Export to Excel" functionality implemented in Python, we go through the process of identifying the problem, experimenting and benchmarking different solutions.
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How to Get the First or Last Value in a Group Using Group By in SQL
Getting the last value of a group in an aggregated query in PostgreSQL is a challenging task. In this article we present a simple way to get the first or last value of a group using group by.
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What You Need to Know to Manage Users in Django Admin
Have you ever stopped to think what staff user can do in your Django admin site? Did you know staff users with misconfigured permissions on the user model can make themselves superusers? Permissive permissions to staff users can cause disastrous human errors at best, and lead to major data leaks and at worst.
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Fastest Way to Load Data Into PostgreSQL Using Python
Explore the best way to import messy data from remote source into PostgreSQL using Python and Psycopg2. The data is big, fetched from a remote source, and needs to be cleaned and transformed.
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Improve Serialization Performance in Django Rest Framework
When a developer chooses Python, Django, or Django Rest Framework, it's usually not because of its blazing fast performance. All of this doesn't mean performance is not important. As this story taught us, major performance boosts can be gained with just a little attention, and a few small changes.
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How to Let Google Know of Other Languages in Your Django Site
If you have a public facing Django site in multiple languages, you probably want to let Google and other search engines know about it.
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- Django, ORM, PostgreSQL, SQL
How to Create an Index in Django Without Downtime
If you ever had to maintain a traffic heavy Django site, you probably had to deal with graceful migrations. In the article I explain what atomic and reversible migrations are, how to execute "raw" SQL in migrations the right way, and how using a little known migration command we can completely alter the Django migrations built-in behavior.
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