Introduction to NoSQL databases

[@RameshAdavi]

Great Teaching Skills. As a 63 year old, I found learning from a youngster, really cool!

[@gkcs]

Thank you!

[@paragsomani5696]

I m 44 but wanted to say the same.Now no need.

[@N_poet]

i m 30+ and fan of them too

[@codelucky]

You're 64 and still leaning. I got to learn from you. Take care, stay safe.

[@pran322]

Me too; learning at 55:-) from GKCS

[@SurajSharma-sd3ws]

Gaurav, you have tremendous ability to articulate modern day computer science concepts. Its great to see someone so young having this charisma and tech flair which is a rare combo. I have been in software for 20 years and sadly i was never taught like this or then around early 2000's there were no youtube channels like yours. You are redefining online learning with your videos. Keep it up mate.

[@gkcs]

Thank you Suraj!

[@tarunpothulapati3425]

Great Video! A small point to add, Most of the NoSQL offerings also offer, Consistency levels for users to choose. So, If I want to make sure my users read always consistent data I can have strong consistency which means a write is acknowledged only when a quorum of replicas have also acknowledged it. This makes sure, consistency is present even when one of the replicas go down. But obviously the tradeoff is the writes are slow. If availability is preferred over consistency, then Eventual consistency can be choosen in which the writes are acknowledged when the present replica writes it in memory, hoping that all other replicas catch up with the write "eventually" .

[@gkcs]

Agree! This is what allows us to aggregate and read fast on NoSQL. I made a mistake in the video by stating that reads are slow. Reads are in fact faster in NoSQL than standard RDBMS as long as consistency requirements are relaxed.

[@lakshaysagarrana3965]

a great summary of cap ❤️✔️

[@InvestWithRishi]

Writes are fast in Cassandra if replication factor is local_One. Although if you change it to quorum then obviously it adds to the throughput of the transaction. It’s all about the system requirement at the end of the day. 😃

[@ananyasharma1201]

@@gkcs Has anything changed with MongoDB 4.2, are the writes any faster considering we get to keep our consistency? Also, We know that NoSQLs go for Availability over Consistency but with MongoDB 4.2, you can guarantee the consistency and also I get to keep my availability by scaling across many shards. MongoDB 4.2 (FULLY ACID kzbin.info/www/bejne/n6bNZXueaqqErNE) They claim that they're "the only database to fully combine the ACID guarantees of traditional relational databases with the speed, flexibility, and power of the document model, and an intelligent distributed systems design to scale-out and place data where you need it." (www.mongodb.com/collateral/mongodb-multi-document-acid-transactions) Which also puts me to a question that why should I use RDBMS over MongoDB when with horizontal scaling I will have a hard time but with MongoDB 4.2 it's built-in with all it brings. Does MongoDB > RDBMS in 2020 after the 4.2?

[@mdxytop]

@@ananyasharma1201 "why should I use RDBMS over MongoDB " -> because MongoDB is buggy as fuck. It's not reliable.

[@andys7384]

It is a difficult skill to be able to understand/comprehend the lower layers of a given technology AND also be able to present it in a clear, concise manner that many can grasp. You have this skill and are able to present the data in a way that is simple with stacks that are complex. This is why being an "instructor" or "presenter" requires skills beyond just knowing the technology really well. Anyway, I appreciate the videos as its a wealth of valuable information!

[@gkcs]

Thank you!

[@azurelearningsimplified1349]

Was just randomly browsing to know about NOSQL and I must say i couldn't move forward without watching full video and I feel confident with the concept. Thank you Gaurav

[@RamziLebanon]

In a strange way, I watched this Video like a proud father lol You are amazing and it shows how much you care to explain rather than show off.

[@gkcs]

Thanks Ramzi!

[@karthikeyansrinivasan52]

When a Non DB guy can understand this.... there is nothing else as better ! Thanks a Ton for you Videos. Your Videos are one of the things that helped me through 2020 Lockdown.

[@MdSheraj]

In Cassandra, “strong consistency” is typically expressed as W + R > RF, where W is the write consistency level, R is the read consistency level, and RF is the replication factor.

[@guruprashanthrao1093]

Truth has been spoken at 9:26 "inner join,outer join,left join the things that we didn't read in college"

[@deeproy7292]

very true bro...after working in a job only we start to get to understand the real use of join and group by😜

[@sandeepmishra5145]

College mai toh kuch bhi nhi batate hume khud hi krna padta h..😅😅😅 gfg h na

[@iamshadmirza]

I am wondering how much time it took you to grasp this much knowledge. Recently followed your channel and it feels like I found a treasure of knowledge. I love to learn and this is a delight.

[@gkcs]

Thank you!

[@deepanshuh_]

Tomorrow is my Big data and data analytics exam and You uploaded this...........what a coincidence!

[@gkcs]

Yey!

[@br34k3r2]

kaisa hua exam XD

[@shubhamqweasd]

Great video as always :D, Just one correction , data is kept in self sorted structures like (AVL/ Red-Black Trees) in memory, and once the memory is past some threshold value (say ~50kb), then the entire memtable(the self sorted trees) are dumped into a SSTable (on disk) which is efficient as the data is already sorted.

[@Happymejoyus]

wow, I am understanding now many things which I had already worked on and faced the technical issues and never used to get the "why" part from my architect's talks. Thank you Gaurav.

[@paulkersey2424]

Then you were never an actual architect. Most people think they are architects, it takes time... Unless you got 20 years in multiple industries, companies, environments you can't be truly an architect. Working in MS, JAVA, WEB, Service, Networking, Infrastructure, CICD, UX, Security from every possible way I think I have a better understanding. This video is your novices or juniors not architects

[@Happymejoyus]

@@paulkersey2424 I'm not.. I was a developer. I mean to say.. my project's architect - my boss. 😳

[@ShubhamJain-kb7zf]

One of the best explanation for nosql over youtube...so far... Keep up the good work

[@gkcs]

Thanks!

[@aishr11]

Superb teaching! Very intuitive, practical and actionable. I'm glad I found this channel & everyone who finds this is lucky. I wish our high school or college teachers would be this adept at teaching. Kudos!

[@vaibhavsouveer]

Great video Gaurav. You have simplified it so much. I have one doubt though... At 6.20 when you are mentioning the 4th point, you say NoSQL are good for metrics/analysis, etc. because it easier to perform operations like average age, total salary, etc. At 7.30 you are saying these are not read optimized because data will have to be read from each blob of data and then perform some operation like sum or average. I am confused about this part.

[@victorcaldentey6295]

About Cassandra, you are explaining the concept of Consistency Hashing, is used in Cassandra but also in many other systems!

[@juancpgo]

Sir, you are truly a great teacher. Thanks for sharing your knowledge so wisely.

[@gkcs]

Thank you!

[@老谈]

This is misleading. Not all NoSQL store data as a key-value pair. What you are talking about is only a subset of NoSQL. There are 4 meain types of NoSQL databases: Document, key-value, wide-column and graph.

[@karthikb6828]

Hi Gaurav, Thanks for this great video and all other videos. I'm extremely benefiting by your videos. Basically, I'm a Mechanical Engineering graduate, with zero CS/dev background but currently work as a Technical Writer with one of top technology Giant in the world. I want to transition to product management and one of areas I lack is technical design. Yours videos are helping me in those aspects. Kudos your great effort. Appreciate every bit of it.

[@gkcs]

Thanks Karthik!

[@rajcodingworld7768]

21:50 Two corrections 1) Cassandra do not store log file in-memory. Rather it stores on disk. That's how it can recover from during failures 2) Cassandra do not append in-memory it rather appends to commit log on disk. So, in-memory the data is sorted Memtable. When it reaches certain limit then it flushes to the disk on SSTable

[@debsworld3784]

Great video , it’s like going back to college after 14 years in the industry .. Thanks and keep it up

[@hellbird1381]

omg bhai..u jus like my frnd who teaches me one day b4 exam and i get salvation enlightened whole universe gets cleared which i try to understand and learn whole 6 months with teachers faculty staff and didn't understand :)

[@msvardhan19]

Hey, Gaurav. I appreciate all of the work you put into this series. I had no prior knowledge of system design, but after watching these videos in 3 days, I was able to pass the system design round at a reputable company. I can't thank you enough for this.

[@gkcs]

That's amazing, congratulations!

[@kratitiwari2850]

Thanks dude for explaining Cassandra in such a simple manner.. kudos

[@naveentrivedi8074]

This is by far the best explanation for SQL vs No SQL DBs. Kudos.

[@prathibhapb]

7:35 - usually most NoSQL databases have secondary indexes that make that kind of querying faster. Great video, thanks

[@NiiAnikin]

Wow. The first intuitive video tutorial on NoSQL ... Finally

[@griseldabalmaceda4943]

THANK YOU SO MUCH!! Read my reading assignment for my NoSQL class and understood most of the things but needed to see all these new concepts in action! Thank you for providing an excellent run through and example! LIKED AND SUBSCRIBED!!!

[@gkcs]

Glad to hear that!

[@pallavisingh2912]

You've made System design a real fun concept to read about! Thanks a lot

[@gkcs]

Thanks Pallavi!

[@learnandsharelive]

How I look RDBMS and NoSQL databases are used based on the requirements or use cases. So, while designing any application we need to understand them first which @GS has done very well. I love your presentation skills @GS and I won't mind mentioning the same in your videos. Keep it up👍

[@ManishPushkarVideos]

Every time I am preparing for Interview, I will revise all the topics by watching your videos. Thanks for the awesome content.

[@justicedoesntexist1919]

The cute double role in the beginning gets me in his videos!

[@susmitapatil4847]

Great teacher I ever saw. I was really confused about the system design concept but after watching your videos it is very clear. Really thanks for such amazing content. Keep doing good work.

[@gkcs]

Thank you!

[@ARCHITSANGHVI13]

The way you represent your knowledge is just amazing. Many people on youtube have good knowledge but don't know how to represent their knowledge to others and explain them. Your way of explaining is just fabulous. Enjoying system design series as a Netflix series. haha.

[@gkcs]

Haha 😁

[@mihirit7137]

the editing in the first 2 mins was on point!

[@rshankarVids]

The video is great, with lots of information, but there are many controversial statements like: 1. Joins are pretty expensive. 2. You need locks to maintain consistency when adding a new column. 3. NoSQL data bases can be optimized for reads. 4. The example taken for the noSQL database is very naive too. You can have N number of columns storing the same data in deserialized format. etc. The video gives a good bookish knowledge but be ready to get cross questioned when you use the concepts.

[@AnkitaNallana]

Great video as always! Really enjoyed the bit where you talk about major applications using RDBMS (the intro). Thank you for this - I learnt a lot!

[@gkcs]

Thank you 😁

[@ArjunSingh-oo1mh]

the great thing in your video is that you give practical examples. THANK YOU. I will continue watching your videos.

[@mathematicalninja2756]

dude this format is awesome i just love your channel man may you get all success in life

[@gkcs]

Thank you!

[@borisvoychev7534]

Great Video Gaurav! I just want to add that apache Cassandra use LSM (Log Structured Merge Trees). The idea is that they want to avoid updating records when using SSD(Solid State Drive) due to the fact that they allow X number of updates before they die. Using LSM they just append new values no matter if they exists or no and as you mentioned they mark the old records with a tombstones.

[@gkcs]

kzbin.info/www/bejne/lWbZo5mrrM2porM

[@viveksharma9564]

Damn!! why does liking something complex gives me a vicarious feel of being intelligent?

[@skdh2006]

Guarav, thank you for the awesome videos. I am applying for entry-level software engineering jobs and this is helping me a lot for companies which test system design skill of their candidates.

[@gkcs]

Great to hear that 😁

[@arezanet]

thank you. i finally understand 'schema'. i'm only 4:44 in, paused the video to post this.

[@designrknight]

Just to put an example, Royal Bank of Scotland uses MongoDB, a No-SQL database. So both SQL and No-SQL are in present day screnario, equally lucrative

[@interviewchamp]

This boy is really good.Great content

[@christophersamk5584]

Regarding quorum of 3 and missing data, if you want your system to be highly consistent, you can do it while writing the data. Say, if you have 3 replicas, make sure the write succeeds only if they data is written on all the three nodes. This obviously has some drawbacks of delay in write but if consistency is all you care about, this approach would help overcome missing data. In CAP, you are compromising on availability here.

[@gkcs]

That's correct.

[@KartheekGanesh]

"Why don't we become optimists as engineers?" 🤣🤣 Yea right I wish. Thanks for the upload !

[@gkcs]

Hahaha 😛

[@jksharma7]

Mr. Gaurav..... You are a BORN TEACHER Sir.... Thanks.

[@gkcs]

Thank you!

[@RohitSharma-cw2ii]

Great little bro..you looks so young but good skill on explanation..

[@gkcs]

Thanks!

[@samarthurs8000]

Greetings from Munich, Germany. Great video Gaurav. It needs a lot of preparation behind such great content. Kudos man!

[@bilguunchinzorig9532]

this is the first IT explanation video made by Indian guy, that I enjoyed watching

[@gkcs]

I hope you find many more in future 😁

[@ansumansatapathy8914]

Maybe start looking at people as the person instead of viewing them in terms of race, nationality, gender. etc.

[@deepak9976]

if your are in java u should watch tutorial from java brains .. ur perception will change.

[@jayaram.ramanarayanan]

11 seconds passed and I gave a like to the video. Great job!

[@gkcs]

😁

[@sdfg204]

Awesome video bro, very simple explanation of pros and cons. Also good coverage with the cassandra cluster. Some add-on information: All companies at this time, do use a combination of these DBs, obviously using RDBMS at priority transactions. NoSQL though is maintained for ever-changing attributes, which are of lesser importance, e.g. Editable/non editable comments, vote count etc., basically every attribute that company can term under eventual consistency(refer computerphile on ytb). The reason here is because of the nature of NoSQL being a document-based db, one could simply queue all the requests onto isps or the client side, and merge these updates in form of an inverted tree. NoSQL is also used extensively as cache for Sql based data, which needs extensive join operations, or simply for basic but simultaneous queries. In this way many companies buy time for development of a proper solution(db/model overhaul is last of them as opposed to the obvious belief) without losing trust amongst consumers. Cluster of NoSQL db would be of slightly much less use than of sql based one. NoSQL is made majorly for handling client-side, because of its state conforming nature. Its a request to discuss master slave db configuration pros and cons too, it makes your Quorom problem both simpler to understand, and also solve the scaling perspective of things, without taking any unusually extra space.

[@gkcs]

I will be discussing master slave soon. I am not entirely sure of your claim that NoSQL is used mainly for client side stuff though 🙂

[@sdfg204]

@@gkcs mostly for handling multiple request from client, do see eventual consistency I mentioned. Obviously, its a tool with many different applications, with good use it can be made out to be anything. Just a noob, happy to learn 😉

[@gkcs]

I see. You are right, it has many applications :D

[@techable7524]

Love your videos dude! Just watched about 8 of them and I now use them in the gym because you can pretty much follow along just listening to you :-) Quick Tip: Set your camera to manual focus and increase the aperture (will keep everything in focus) a little as your camera 'hunt's for focus and is a bit distracting on the eye. Love the quality your producing so please keep them coming!

[@gkcs]

Thanks! I'll make sure to apply these tips 😁

[@gero8049]

Thats the first introduction that was acctualy an introduction. Great Video.

[@rakshitkoyani1655]

nice explanation. now a days very few teachers teaches on the board which is easy to grab a concept at 1st pace

[@amith1989]

This is the first video of yours that I saw but amazing way of explaining bro. This video is great for someone like me who had absolutely zero idea about NoSQL Databases since I have always worked with Relational Databases only. Subscribed!

[@anastasianaumko923]

Introduction is hilarious, so cool 🤣🤣🤣 The video is elaborate and educative, thank you! 🤩

[@killbuzzygamer3220]

sir bohut badiy TARIKE SE explain kiya hain apne ......dhonnobad

[@SarabjotSingh294]

Truly amazing video. So perfectly described NoSql and RDBMS. Thank you so much.

[@logicsandtrolls3616]

Nice. You could add below - 1. NoSql might have a upper limit on amount of data you can store. 2. If you have to write to multiple tables/rows at the same time and do like a group commit, this might get limited in noSql.

[@fsl4faisal]

the beginning was some ninja editing skills..!! the video as always very informative.. Thank you..!

[@gkcs]

Thank you!

[@swarajgupta3087]

Thanks Gaurav ! Quorum: सदस्‍यों की वह न्‍यूनतम संख्‍या जिसके होने पर ही बैठक में निर्णय लिए जा सकें !

[@gkcs]

Wow!

[@Manwithsteelnerves]

Upcoming video idea : Give a brief on all current trending databases, pros and cons and when to pick each

[@starlord9220]

😍ur content quality is increasing + information provided is clear

[@gkcs]

Thank you!

[@ru2979]

The plot of this video is dope 🔥🔥🔥

[@navjhs]

Gaurav....you are just awesome. What a great skill you have. Thank you.

[@MrJosejohny]

Very crisp, clear and simple explanation Gaurav Sen ...Thanks a lot...

[@yashjain-wj1eg]

Thanks man! I was asked sharding and sql vs no sql in my interview and was able to answer them perfectly and crack the interview as well. Thanyou Again.

[@gkcs]

Yey, congratulations 😁

[@yashjain-wj1eg]

@@gkcs keep making such videos to help students like us! Thankyou!

[@dhananjaynagargoje6487]

Saturday morning breakfast while watching your video 😁

[@md.abdullahal-alamin8059]

Great video. Please make a detailed video on Redis or distributed cache system

[@gkcs]

Coming up 😁

[@JoseBlanquicetM]

System Desgin is a great playlist. I am using it to get prepared for my interview. Thanks! Just one suggestion: I think you should talk a little bit slower, it's too much information to process so talking slower will allow people watching the video without need to stop it, analyse what you said and then resume the video :) ... It's just my opinion

[@gkcs]

Noted!

[@serez18]

Great video. Very informative and well organized! I'd like to update that RavenDB is a noSQL database that offers ACID certification for transactions.

[@adnanbadar6981]

Very Precise, Keep it up Gaurav. Excellent Job!

[@vmohakrish]

vow are your videos always so fun.Dont know how I got to know this channel to late

[@AndhraKitchenFoods]

Excellent presentation on NoSQL DBs.

[@Manu-mr4mn]

Wow usually I avoid videos with people who are Indian or something like that, just because the accent is hard to understand and the quality is not so good. But this video is amazing! Great job, I’ve subscribed!

[@gkcs]

Thank you 😁

[@Manu-mr4mn]

Gaurav Sen No problem! Great content I like your channel. I would love to see more videos like this! :)

[@gkcs]

@@Manu-mr4mn They will be coming soon!

[@NileshwarShukla]

Apart from technical expertise you are also trying to specialise in video effects 😊

[@gkcs]

Yup!

[@fiveyearclub6024]

Another awesome video. I've been using mongodb successfully for 6+ years but never got into the weeds about how it compared to MySQL.

[@abhijitghatnekar9347]

Great video, Gaurav! I wanted to add a point. In the video you mentioned a disadvantage that Joins are hard in NoSQL. When you're dealing with extremely large data-sets, you probably would want to avoid joins. If you -use a NoSQL database in a relational manner, i think its probably not worth it. In that case, you're better off using an RDBMS..

[@bonniwanamaker6296]

Hey this is great refresher. Not only is it well explained but you make it entertaining :) Keep it up!

[@paragsomani5696]

You are doing a super work in a super excellent way.Best wishes.

[@mufty9006]

The intro was extra fun😀 and educative I LOVE IT❤😂

[@umaer2044]

@Gaurav_Sen bother hope you are doing well. I just saw you on KZbin.. I really appreciate for what you are doing... Sharing knowledge.. 🙏 🙏 🙏 🙏 🙏.

[@gkcs]

Thank you!

[@denniszenanywhere]

Best explanation of nosql and mysql

[@saebalam2498]

You seems so knowledgeable and professional ❤️

[@TusharParekhtpar2014]

Very Good explanations and correlations . Thank you very much for the knowledge shared !

[@saurabhsingh7020]

Hi Gaurav, Really nice video. It must have taken lot of effort. One point, Consider situation of altering a table and adding salary column. In SQL it will acquire lock and slow the process. In NoSql it will faster. But column won't be added in all pre existing documents. In will break backward compatibility if user tried to fetch salary from any pre existing document. Thanks

[@gkcs]

Thanks Saurabh! Yes it would, and that's one of the issues with constraint addition here. A check for null with a default value could be added in the application layer perhaps?

[@saurabhsingh7020]

@@gkcs Hi Gaurav, In SQL queries present in our code will throw ColumnNotFound. Don't know how we fetch in NoSql. Maybe due to json structure, we get that flexibility.

[@gkcs]

@@saurabhsingh7020 Yup, we do. Hence the flexible schema.

[@ravindracute]

I really like the way you explain Gaurav....

[@ravindracute]

I have been extensively working on Cassandra and it is really a boon for NoSql DB

[@shubhranshukumar1814]

I am kind of confused that how No-SQL databases can have the read time as a disadvantage along with data aggregation as an advantage. Isn't a lot of read required for aggregating the data?

[@amythpaddy8527]

Same question. And from my experience I did not find data aggregation easy for nosql data. Am I doing something wrong?

[@sigfrido86]

I think that the key is database sharding and partitions. If you don't take this into account, read across partitions its a very expensive operation. If your database is well design, then you are ok.

[@vitthalsarode5149]

@@amythpaddy8527 I think what Gaurav means is most of NoSQL databases give inbuilt support for aggregation like mongo. Please go through this link you might get your answer docs.mongodb.com/manual/core/aggregation-pipeline/

[@obiwon84]

I think read performance can vary a lot for each NoSQL database. To further complicate the matter small reads vs large batch reads could have vastly different performances. Data aggregation tends to be large batch reads I would assume. Perhaps that is the reason for his statements?

[@Manoj-tb1lv]

if consistency is relaxed, then read is faster in Nosql, else consistency adds an overhead .

[@ujjwal94roy]

Amazing explaination for a noob. Nice job

[@gkcs]

Thanks!

[@togadiadarshan4732]

Great video. It helps a lot to understand the system design concepts. Can you please make a video on how node and react use event-driven architecture?

[@gkcs]

Thank you! I have one on event-driven architecture here: kzbin.info/www/bejne/qHurhX5oicuNZ6s

[@starkhunt2684]

Bro you should upload 1 min or 30 sec separate video of that intro clip which discusses Difference between NOSQL & SQL!! It is great🤣🤑

[@myth00s]

The term "relation" in RDBMSs does not refer to the referential integrity achieved with foreign keys, but to the structure we more commonly refer to as "table" - a set of rows / tuples.

[@rajeshpothamsetty4830]

Thanks for video @Gaurav. query: If read times are slower in NoSql, how is it that it is good for aggregations? If I want average age per city, I still have to go through all records and and entire blob for each record, this is expensive right? Can you elaborate more on this?

[@vimleshkumarkanaujiya]

Bahut Sahi Kar raho Ho Sen Bro. People want videos from video. Expectations from you.

[@Arneboy98]

I wish my class was this interesting.

[@sachin.tandon]

Thank you Gaurav. A very impressive educational video! Keep up the great work!