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Hi, Suppose there are two tables A and B. Each table has only two columns, ID and NAME. We have to get an output table that has rows in it as : 1st row from A 1st row from B 2nd row from A 2nd row from B 3rd row from A 3rd row from B .... and so on. What would be the query to generate this output table?

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@@TheMLMine thanks

Thanks. Glad it was helpful

When doing self-join every manager id was matched with every employee id, thereby also matching the manager id of Anurag with the employee id of Akshita. Whereas, in recursive CTE when we start with Rakesh (given emp id), we first match the manager id against Rakesh with the emp id of Shiva, then manager id against Shiva is matched with the emp id of Satyam, and so the chain builds up. The catch is, since Anurag's emp id is not the manager id of anyone in the chain, the entry for Anurag is not included. Thereby giving only 4 entries (which are part of manager - emp id chain) Hope it helps

Thanks priyanka. Glad it was helpful

Hello, yes stats are an important part and will be covered soon. Thanks for mentioning it.

Thanks for your feedback. I will come up with videos on that topic soon.

Good question yashika, - if nothing is specified (on which row to delete) : If you observe the row_num entries > 1 are the entries that may have been inserted at a later stage. You may justify to the interviewer that we are deleting only the latest rows if they are repeated, keeping the originally entered row (row_num=1) as it is. - If interviewer asks you to keep specific rows based on emp_id among the repeated values, you can simply do DELETE FROM emp WHERE emp_id IN (<id provided by the interviewer>) - I am not sure how you are thinking to use rank or dense_rank because you will need to anyways select which rank value to keep and you don't know at what rank the same values are there. However, in all the cases, you will either use emp_id column (since that is the only unique column we have) or a self created column (either row_num/rank/dense_rank) based on the type of row to delete. Hope it helps. Let me know if you have any further queries

Thanks akash. Good to know

Thanks. My pleasure

Thank you @yash. Glad it was helpful.

@@TheMLMine I have been looking for you on Instagram or LinkedIn so I can chat with you. I wanted to learn more about the data analyst field. If possible sir ?

Sure, you can connect me over 1) Linkedin: www.linkedin.com/in/ritesh-yadav-29745112a/ 2) Instagram: instagram.com/the_ml_mine/

@@TheMLMine thank you so much sir, I'll message you on LinkedIn 😊

It's published now :)

Hi akash, This error is because MySQL safeupdate setting is on. Safeupdate restricts certain types of queries that can unintentionally affect a large number of rows while deletion. And, using a WHERE clause with condition on a non-key column (that can have repeated values) could be one cause of that. What can you do? For now, you can turn the setting off in Edit->Preferences->SQL Editor->Uncheck Safe Updates (you can find the checkbox at the bottom most position in the window). Then restart MySQL and try again. Your query should work. Let me know if you face any issues

Hi Shubham, so the idea was to cover basics for beginners. If you have any specific topics that you think should be covered, do write them below. Thanks

Glad to hear that

@TheMLMine sir how can i connect with you over the Instagram.

Hi raj, if you have any interview question related to any health care project, please let me know. I can make a separate video on that.

Thanks ankit. Glad it was helpful

Thanks Akash. Glad it was helpful

Thanks anand

Thanks vaishnav

Thank you so much. Glad it was helpful

My pleasure

Sure. I will try to summarize the SQL learning as a roadmap in a separate video. Thanks for your feedback

Thanks bro

Thanks. Glad it was helpful

Hi ankit, you are right. You can use dense_rank method as well. The only difference is if revenue of two products are same they will get the same rank value when using dense rank function while they will get different rank values when using simple rank function.

Feedback noted

Thanks. Glad it was helpful

Yes, you are right. However, "DELETE FROM CTE" is not supported in mysql, so we can not use that method here.

@@TheMLMine yes this will be useful for SQL Server users

Sure shubham

Hey Hari, you can refer to this website: sqlbolt.com/ for basic sql queries. For creating your own tables on server, refer this: www.sqlwebadmin.com/ (Although, I never worked with this before) Hope it helps.

@@TheMLMine thanks so much response already try this but didn't get sql advance please help these

@@HariharanTamilarashanJeyasri No problem, can you please elaborate what do you want to achieve? Do you want to use cloud-based SQL database? If yes, are you willing to pay some subscription amount as well?

@@TheMLMine thanks actually I am looking leaning sql advance function and practice plateform as well

Hi Hari, sorry somehow missed your comment. So, for the web based advance sql you can refer below links and choose your difficulty accordingly: 1) HackerRank - www.hackerrank.com/domains/sql 2) SQLPad - sqlpad.io/ 3) LeetCode - leetcode.com/problemset/database/ Hope it helps !

Hi Karthipalanivel, I could do that but different servers support different syntax of queries. So, I could not do that in the same video. But, I will see if I can cover it in my upcoming videos. Thanks for your feedback.

Thanks. Glad it was helpful

Hi Nishant, it is normal in the beginning that it will take time to solve queries. That is why we need practice and practice. My suggestion would be to also understand the order of execution in which the commands are executed. It will help you understand the function of each commands and what happens in the backend (with order). You can refer this link, if it helps: sqlbolt.com/lesson/select_queries_order_of_execution And please practice questions without jumping at the solution and then understanding it backwards. Try to solve them by yourself first, be it wrong or right. Let me know if you need further help

Thanks. And you are the 1000th subscriber