Recent Posts

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.

Please make use of my blog posts for learning purpose only and feel free to ask your questions in the comment box below in case of any doubt.

Click Here for the previous blog-post in the series.


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:

CITY Columns




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.




Sample Output:

6

--------------------------------------------------------------------------------
Click here to see solutions for all Machine Learning Coursera Assignments.
&
Click here to see more codes for Raspberry Pi 3 and similar Family.
&
Click here to see more codes for NodeMCU ESP8266 and similar Family.
&
Click here to see more codes for Arduino Mega (ATMega 2560) and similar Family.
Feel free to ask doubts in the comment section. I will try my best to answer it.
If you find this helpful by any mean like, comment and share the post.
This is the simplest way to encourage me to keep doing such work.

Thanks & Regards,
-Akshay P Daga

No comments