What is NULL, NVL, NVL2, Coalesce in SQL? Why it is important to handle NULL?

What is NULL, NVL, NVL2, Coalesce in SQL? Why it is important to handle NULL?
www.testerhoon.com
#sql
#etltesting

[@SANJAYYADAV-hm2bs]

Contents of this channel are ready awesome. The way of explanation really cool. I love to watch all the vides of this channel as ETL tester.

[@testerhoon28]

thank you 🙏

[@smiley1059]

Thanks a lot. I am a new learner for ETL Testing. For interview preparation using your shared experience, knowledge. Thank you again.

[@testerhoon28]

Thank you 🙏

[@sachin.personal661]

what a voice dear mam😘😘😘😘

[@testerhoon28]

🙏☺

[@thelayer5211]

Good 👍

[@RakeshKumar-ql6oi]

Please upload the videos in English ...your content and explanation is good...

[@vasugin2734]

Please explain in English it's very useful

[@gullasridhar8720]

mam by default null is considered as highest value or lowest value in the database.

[@testerhoon28]

Null means nothing, its just a placeholder ...

[@dattabandi9226]

Good morning mam
as etl tester which AWS services we should know for performing task.

[@testerhoon28]

I mostly work on Azure services not on AWS, so could not answer ur question 🤐

[@dattabandi9226]

So which services from Microsoft Azure should I learn as etl tester.
Mam please upload videos regarding etl automation.

[@dramatv9122]

​@@testerhoon28which azure service we should learn first

[@Manifestion_kannada]

My when hiring will start after March??

[@thelayer5211]

May be whole year aise hi chalega

[@testerhoon28]

No idea... now a days firing is going on... all new hiring is freezed... 🤐

[@My-Research]

can Coalesce and NVL2 both are performing same work ?

[@kirankalliguddi3617]

I think COALESCE returns column's first non null values and NVL2 replaces null values with your values??

[@testerhoon28]

yes right !