Basics of data warehouse and ETL testing

I have created this video for software testing professionals, who are beginners with ETL testing. 

In this video, we will go through the basic concepts of database, date warehouse and SQL queries required to perform ETL testing.

Agenda includes introduction of database, data warehouse and basic difference between them.

We will go through ETL based data warehouse architecture, which talk about ETL process.

We will have a look at the concept of dimensions and fact tables, which are part of data warehouse.

ETL testing approach along with basics of SQL queries will be seen. At the end, we will have look at simple automation method for ETL testing as well.

https://youtu.be/jor49_utDlU

Note that only theoretical points will be explained in this video, as it is not feasible to show you test execution of actual live project due to multiple constraints.

Overall, this video will help students as well as those who are seeking ETL testing interviews.

If any question/clarification, please let me know in the comments section below.

What is TDS of water and how to use TDS meter

Here is the quick video to understand what is TDS of water and how to use TDS meter.

TDS stands for “total dissolved solids” which represents the total amount organic and inorganic salts dissolved in water.  Human body needs certain proportion of these solids in drinking water though.

According to World Health Organization, TDS level less than 300 mg/litre is considered as excellent, between 300 and 600 mg/liter is good, 600-900 is fair, 900 -- 1200 is poor and TDS level more than 1200 mg/liter is unacceptable.

 

Most of the cities are getting municipal water supplied to us within TDS value ranging between 150 to 180. For these TDS values, usual UF filters or UV filters will serve the purpose to eliminate the contaminants, I order to make water safe to drink.

This is the basic reason on National Green Tribunal's order prohibiting use of reverse osmosis (RO) purifiers where total dissolved solids (TDS) in water are below 500 mg per litre.

https://youtu.be/n-50_Zxdj-c

TDS meter you see in video is completely made out of plastic. It has got ON OFF button. When you turn on, it reads 0 PPM.

Demo is shown on municipal water , Kaveri water, which reads 115 PPM as TDS value which is safe drink but not as is. You need filtering with either UV or any gravity or even traditional filters. 

Pressing hold button on TDS meter will just store the current TDS value.

This TDS meter comes with additional functionality of checking the temperature of the room or hall. There is case cover bundled inside the pack of this TDS meter.

Overall, I found the readings accurate all the time when I compared with other TDS meters and found it value for money. 

Amazon link to this product and UF/UV water purifiers : 

TDS meter @ Amazon India: https://amzn.to/3btu40R

Gravity based water filter @ Amazon India - 

Eureka Forbes Aquasure from Aquaguard Amrit 20-Litre Water Purifier: https://amzn.to/2UMs8KY

UV + UF water purifier with storage tank @ Amazon India -

KENT Maxx 7-Litres Wall Mountable/Table Top UV + UF (White and Blue) 60-Ltr/hr Water Purifier with detachable storage tank : https://amzn.to/39wZQbJ

How to install LED dome map interior light in Maruti Suzuki Celerio or any Maruti cars |~INR rs.100

Here is the quick video on how to replace dome light or interior roof light in Maruti Celerio. 

Steps remain almost similar for other car models.

https://youtu.be/7swO_qCBuKk

Amazon link (seller : Cloudtail india) ~rs.100

Generic led car bulb 31mm 3528 16 leds smd dome map interior light lamp 12v white

https://amzn.to/37Z0eyZ

Note: 

1. Use both the hands to fit, as it's difficult to do it single handed and it may result in damage. I've skipped few frames in this video when fitting.

2. Suggest you to buy from the seller CLOUDTAIL india on Amazon. Refer above link.