SQL 50 Summary Basic to intermediate SQL topics 50 essential SQL questions Best for 1 month of prep time

Advanced SQL 50 Summary Basic to advanced SQL topics 50 high-frequency SQL questions Best for 1 month of prep time

Can you solve this real interview question? Recyclable and Low Fat Products - Table: Products +-------------+---------+ | Column Name | Type ...

Write an SQL query to find for each month and country, the number of transactions and their total amount, the number of approved transactions and their total amount.

This is a very good example to show the performance of SQL code. Try to work out other solutions and you may be surprised by running time difference.

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Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview.

Can you solve this real interview question? Students and Examinations - Table: Students +---------------+---------+ | Column Name | Type ...

Write an SQL query that reports the average experience years of all the employees for each project, rounded to 2 digits. Return the result table in any order. The query result format is in the following …

In SQL, id is the primary key for this table. id is an autoincrement column starting from 1. Find all numbers that appear at least three times consecutively. Return the result table in any order. The …