SQL Essentials

This page is dedicated to SQL. As SQL is very essential part of any job in IT that you can think of, I have decided to put important content of SQL on this page. I'll mostly focus on interview oriented content so that it'd be useful for jobseekers; they can get most out of it quickly and in most easiest way possible.

I'm trying to put some Leetcode problems here and checking if this gets good response, after that will start putting concepts with examples. Some examples from Leetcode can be discouraging for many of the students but trust me SQL is most easiest subject to learn and it can land you most lucrative job offers as well, so don't get discouraged easily just keep learning and practicing to write queries. Hackerrank is best place to get started for newbies.

1. Combine Tables. Leetcode Problem.

2. Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.

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