NULL SAFE Join - Tricky SQL Interview Question🔥SQL Joins - No One Will Tell You This❤️Data Engineer🔥

[@shashank_mishra]

How many of you already knew about Null Safe Join? Let me know in the comment section

[@debajyotideba5001]

Sir , please make a set of SQL problems sheet basic to advance for Data Engineer ❤️. In the market there are bunch of SDE sheet for SDE, but for DE there is no such sheet for Aspiring DE. So, please make it, it will be helpful for all the Aspiring Data Engineer ❤️💙

[@vineetpandya1306]

I had no idea about this concept at all!! Thanks Shashank so much....you're literally updating us about all these tricky interview cases free of cost 😇

[@VedanttMehtaa]

create table tableA(colA int): create table tableB(ColB int); insert into tableA(colA) values(1),(2),(1),(5),(NULL),(NULL) insert into tableB(colB) values(NULL),(2),(5),(5);

[@sanjeevrana1954]

Thank you!!😀

[@debajyotideba5001]

Sir , please make a set of SQL problems sheet basic to advance for Data Engineer ❤️. In the market there are bunch of SDE sheet for SDE, but for DE there is no such sheet for Aspiring DE. So, please make it, it will be helpful for all the Aspiring Data Engineer ❤️💙

[@ravindra2141]

as soon as i heard null safe , COALESCE was the first thing that came to my mind .

[@gurramvarunchowdary5735]

Exactly 😀

[@anjanguharoy]

You mean select * from tableA inner join tableB on coalesce(tableA.colA,'')=coalesce(tableB.colB,'') ? Considering colA and colB are string

[@gurramvarunchowdary5735]

@@anjanguharoy yes

[@shashankemani1609]

I didn't know about null safe join at all. And not sure how we can use coalesce here. I don't think it's useful in this case. As always superb thank you! Please come up with more such problems 🙏🏻

[@hdr-tech4350]

tableA.colA == tableB.colB or (tableA.colA is null and tableB.colB is null) ; null safe join Operator

[@avilashsadual3393]

Instead of long or operation:select * from tablea a, tableb b where nvl(a.cola,'awe') = nvl(b.colb,'awe');

[@mbkamath3720]

Mind blowing!🤯🤯🤯thank u Shashank for these kt..hungry for more..

[@prathamIsOp]

I was asked this question in my interview and i answered with null getting matched with the null. Now i have finally understood how to handle null values with inner join.

[@ThePragyashree]

So good... I really didn't know about null safe logic... Thank you so much.. 👍

[@AbhishekSharma-sr6mh]

You can also use something like this in ON clause, single condition- ON ISNULL(ColA, 9999) = ISNULL(ColB, 9999) **9999 is just an arbitrary value for the sake of join whenever NULL value is encountered.

[@millennial_post]

This totally new problem statement for me...thanks for the detailed information.

[@ramanreddy7276]

postgresql with cte as ( select COALESCE(v1,0) as v1 from t1 as a1 ), bb as ( select COALESCE(v1,0) as v1 from t2 as b1) select * from cte as c1 inner join bb as d1 on c1.v1 = d1.v1;

[@aman6646]

Can you make a similar video on that question from your Amazon data engineer interview which was about table a and b something about plane ?

[@navjotsingh-hl1jg]

sir where all this things learn from?

[@hariomawasthi2675]

Really enjoyed the way you explained the concept ...very simple and easy to understand

[@databridge9580]

You could have used NVL for that , again it's in Oracle, don't know what is there in my SQL

[@VamsiKrishna-je3iy]

Kindly do video on aggregate function like department wise in various combination ur video of joins helped me a lot

[@manunair3327]

Sir could please share any platform name where we can practice these kind of questions ? Please reply thanks in advance

[@eshakhosla1]

Hi. Thankyou for sharing this useful video. Also, I have one doubt if you can help - What will be the result if left/right joins are applied to these two tables?

[@Datapassenger_prashant]

Main thing is , asking the questions from interviewer. This concept was not known to me as well ..

[@chirag1688]

Your videos were very helpful for me to get motivated keep it up brother...❤

[@forniteguruji9409]

Hey Shashank, Is there any good source to practice or get to know these types of tricky questions for FAANG level preparation?

[@shashank_mishra]

Sadly nothing as such available

[@pankajdubey1123]

thanks sir for this content

[@deepanshusingh6057]

Interesting , thanx

[@sravankumar1767]

Superb bro 👌

[@smileplease6151]

Thank you so much bro

[@subhojitpaul5527]

Very informative

[@sudharsanaragavendra1213]

Hi mr.shashank Is engineering degree is must to become data engineer?.

[@jignesh1001]

Why didn’t u use isnull or coalesce operation..

[@ravinarayan1008]

Hi sir, I am a SQL database developer and wants to get into data engineer profile ,plz guide me.

[@sagaragarwal5705]

Hi sir, please make more videos on sql

[@SunilVerma-qg8bb]

Can we use WHERE statement instead of OR

[@francis.joseph]

what is the use of null safe joins

[@ganaparthijagadeesh]

Isnull in sqlserver

[@sravankumar1767]

Keep posting new videos 📹 ✨

[@taniyasaini6830]

cant we use IFNULL or ISNULL?

[@powerfullifehacks7238]

Hi Sashank, can you suggest me a course to crack Data engineer roles in FAANG level companies. Plz🙏🙏🙏🙂🙂 -currently I am working as azure data engineer

[@shashank_mishra]

There is no dedicated course for it but I have created a roadmap for the same

[@powerfullifehacks7238]

Thanks Shashank for your reply

[@dv584]

Similar experience,, I had two interviews with two different companies .... in the first interview the interviewer asked a question related to Lead and Lag functions (I have never used them and hardly know about them in SQL server), I was not able to solve it.. the later day in another interview i had similar question from another level 5 company.. luckily i was able to answer it as i already had learned after the previous interview.

[@forniteguruji9409]

what is level 5 company?

[@Sharmasurajlive]

👍🏻

[@VamsiKrishna-je3iy]

In struggling with it

[@hirenvjaiswal]

Awesome @shashank