HackerRank: [SQL Aggregation] (1/17) REVISING AGGREGATIONS - THE COUNT FUNCTION

I started studying SQL from a very famous site - HackerRank. Here I will try to provide multiple approaches & solutions to the same problem. It will help you learn and understand SQL in a better way.

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Recommended SQL Courses:

1. Udemy: SQL - MySQL for Data Analytics and Business Intelligence
2. LinkedIn: Master SQL for Data Science
3. edX: Databases: Advanced Topics in SQL
4. edureka: SQL Essentials Training & Certification
5. Coursera: Learn SQL Basics for Data Science
6. Eduonix: SQL Queries

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SQL Problem Statement:

Query a count of the number of cities in CITY having a Population larger than 100,000.

Input Format:

The CITY table is described as follows:

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Solution: Using COUNT Function (MySQL Query):

SELECT count (*)
FROM CITY
WHERE POPULATION > 100000;

NOTE: 

1. COUNT is an aggregation function used to calculate the count of the number of records in the specified column name passed to the function.
2. "*" (asterisk character) is used to pass all the column names of the table.

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Sample Output:

6

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-Akshay P Daga