SQLite3: Python and SQL
Everything we did in last articles of the series SQL-Tutorial was a dry run because we just used SQLFiddle. So let’s start with a real database like SQLite.
SQL-LIKE and wildcards
This article is part of my SQL-Tutorial Motivation Sometimes you need to retrieve data from a database without knowing the exact string to look up so wildcards for the rescue Underscore Se_en represents a pattern with a wildcard character. The _ means you can substitute any individual character here without breaking the pattern. It matches…
SQL-Basics: Relations
As the Junior Data Scientist of Knight Industries we created a table to keep track of all our operatives: SQL-Basics: Create, Read, Update, Delete Devon asks us to keep track of our operations aka missions as well. For the first implementation let us assume that a mission has one operative and an operative can participate…
SQL-Basics: Create – Read – Update – Delete
This episode is about the basic statements needed to create, read, update and delete data in a database system. It is part of my SQL-Tutorial Motivation Let’s assume we work as a data scientist for Knight Industries. We want to help the Foundation of Law and Government to keep track of our operatives. We decide…
SQL-Basics – Subqueries: Update column with values from another column
Sometimes You screw up your database design and you have redundancies i.e. your database is not normalized. If You want to correct that: Subqueries for the rescue! In our example we have two tables which contain almost the same information: CREATE TABLE installed_device (`id` int, `device` text, `info` text); INSERT INTO installed_device (`id`, `device`, `info`)…