An easier way to explain indexing is to compare it to a book. A book has an index page that shows where to find the topics in a book. So, instead of you going through the entire book to find the topic you're looking for; the index page helps you know where exactly that topic is. Saving you time. Therefore, same thing with SQL queries.
I have to disagree with you, your example is intuitive, but it doesn't explain how and why index is fast. Although index has fewer pages than actual table, but what if your table is huge, and index from this table has a lot of pages? it is still slow (of course faster than scan the whole table) to scan all the pages in the index. And in SQL Server, there is a type of index called clustered index, which stores the whole table data in it instead of a seoarate structure beside table data, so it is basically your book with all the pages and no index section. Other point is indexes are stored on disk just like table data, so no hardware advantage. What make index fast is how the data is stored, data is stored in B+ tree structure, which make seek operators fast.
My name is Femi from Nigeria. I love data analysis because it's enables organizations/businesses get better understanding of its data and make informed decisions with it.
Dude, you’re here to save the day, you don’t even need someone to ask for something you upload the most awesome content, was in the bank the other day and the banker asked me about DataAnalysis content i was just about to recommend your channel but the guy already knew your channel had the best content, Greeting from Egypt 🇪🇬, God bless you and your family Alex ♥️✨
My name is Angela from Nigeria. watching your video has really helped me a lot in my career as a data analyst. Though am taking courses on coursera yet i come to watch your video for more clarity. Thanks Alex.
This is, by far, the greatest Content Creator I've ever found. I'm not exactly a techie, but to avoid ending up on a soup line, I've been learning marketable skills. It's not so common for an individual to be both well-versed in dense techie topics & able to explain it in a brief, understandable, and practical way, but damn, Alex the Analyst... *Thank you*. (No, I wasn't given anything to write this, but am compelled to do so after viewing ATA's content versus those of others, which can be laughably unclear).
21:55 was such a helpful explanation to better understand what a join does when connecting IDs! love the video! and 53:30 is also super important and good to know for understanding employer expectations!
Hello Alex, I just found out about your channel, and I am impressed with what I have seen thus far. I’m currently studying: CompTia A+, Network +, and Security +, in hopes of changing careers from elementary education to the IT industry. Thanks for all the great information! Jalapeños!😊
Easy as you like it..sleek yet most effective...even slides are designed and curated in a way that explain almost everything related to the topic at first glance...you are the champ bro...
Hi! So happy to be joining. Yemi from Nigeria. I decided to make a 360 degree shift from a completely different field to tech so I get to know more and grow in the data analytics. Hoping to have a substantial amount of knowledge of SQL as a beginner.
Hi Femi, i just came across this video today and going through the comments i saw yours and chibuike’s. I wouldnt mind going the team as i making shift too from a totally different career. Hope you dont mind?
Even if i have any difficulty understanding what our tutor says, I'm always running to Alex videos, funny enough, he recommended his video for us some days ago😊
I wish I could spend some time with this guy. I would put myself at probably an intermediate skill level with SQL which is one of my main functions in my job... but I have a lot to learn.
I am in the middle of the Data Analysis course with Coursera. This video has been a great way for me to further review the SQL portion of the course. Thanks for uploading.
I honestly don't why the sudden fascination with data analytics. All I know is, it's getting crazier by the day. But with Alex I'm getting better and better!
13:23 What was the purpose of the 'AS salary' statement here? I don't quite understand the meaning of 'naming' an output as it is being used here, since 'AVG(salary)' could do the job, maybe? Awesome work you're doing here, Alex! Thanks!
You don’t have to include the “AS salary”, but it’s good practice to explicitly define the column name when you use a function with “group by”. If you remove “AS salary” from the query it will still give you the same output, BUT the second column wouldn’t have a name (in SQL Server it would display “No Column Name” for the second column). Just a side note: In his example, it would’ve improved readability if he used “AS avg_salary” instead.
Hello Alex, the content is amazing. Congratulations! 31:13 Could you please recommend some tools to help me to identify the bottlenecks to optimize my queries? Thank you so much
my name is jaiyeola aminat i love data analysis because anaything can happeng will be abale to solve problem easily eg problem like customer behavior analysis, product performance, financial analyst. etc
I started programming around 12 years old. I've been a software engineer for 20 years (C# and SQL mainly). In college I had to take Calculus and Statistics to get my CS degree. Waste of time! I've worked and major Banks and Insurance companies. I don't think I've did much above basic algebra. As long as you know the logic the computer will do it for you.
I really wanted to complete the course. But I use Mac M2. I think I am not having proper guideline about how to setup. I tried through docker and terminal command. It was going okay until my azure studio is not able to find my localhost and could not get connected. I wish I could get a solution of the pretty unknown problem.. :(
I really appreciate this video but it has a title that’s not quite right. The only thing that is advanced is window function and there is a very short mention about it.
![SQL Course for Beginners [Full Course]](http://i.ytimg.com/vi/7S_tz1z_5bA/mqdefault.jpg)
An easier way to explain indexing is to compare it to a book. A book has an index page that shows where to find the topics in a book. So, instead of you going through the entire book to find the topic you're looking for; the index page helps you know where exactly that topic is. Saving you time. Therefore, same thing with SQL queries.
This was a really good comparison,👌🏽
I have to disagree with you, your example is intuitive, but it doesn't explain how and why index is fast. Although index has fewer pages than actual table, but what if your table is huge, and index from this table has a lot of pages? it is still slow (of course faster than scan the whole table) to scan all the pages in the index. And in SQL Server, there is a type of index called clustered index, which stores the whole table data in it instead of a seoarate structure beside table data, so it is basically your book with all the pages and no index section. Other point is indexes are stored on disk just like table data, so no hardware advantage. What make index fast is how the data is stored, data is stored in B+ tree structure, which make seek operators fast.
My name is Femi from Nigeria. I love data analysis because it's enables organizations/businesses get better understanding of its data and make informed decisions with it.
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🇳🇬
Who asked?
❤
Dude, you’re here to save the day, you don’t even need someone to ask for something you upload the most awesome content, was in the bank the other day and the banker asked me about DataAnalysis content i was just about to recommend your channel but the guy already knew your channel had the best content,
Greeting from Egypt 🇪🇬, God bless you and your family Alex ♥️✨
My name is Angela from Nigeria. watching your video has really helped me a lot in my career as a data analyst. Though am taking courses on coursera yet i come to watch your video for more clarity. Thanks Alex.
Yes o! So helpful! Thank you!
This is, by far, the greatest Content Creator I've ever found. I'm not exactly a techie, but to avoid ending up on a soup line, I've been learning marketable skills. It's not so common for an individual to be both well-versed in dense techie topics & able to explain it in a brief, understandable, and practical way, but damn, Alex the Analyst... *Thank you*. (No, I wasn't given anything to write this, but am compelled to do so after viewing ATA's content versus those of others, which can be laughably unclear).
21:55 was such a helpful explanation to better understand what a join does when connecting IDs! love the video! and 53:30 is also super important and good to know for understanding employer expectations!
Hello Alex, I just found out about your channel, and I am impressed with what I have seen thus far. I’m currently studying: CompTia A+, Network +, and Security +, in hopes of changing careers from elementary education to the IT industry. Thanks for all the great information! Jalapeños!😊
Thank yu so much for having this up. I love data and facts, it makes the world go round.
HOLY SHIET! This is PHENOMENAAL
Hello, my name is Jonathan from Nigeria. This is my last class with Alex on SQL, I watch all his videos so I’m happy to be here.
New subscriber and this is my first video. Great content.
Easy as you like it..sleek yet most effective...even slides are designed and curated in a way that explain almost everything related to the topic at first glance...you are the champ bro...
from Myanmar, Thank you very much for the channel!!!
Hi! So happy to be joining. Yemi from Nigeria. I decided to make a 360 degree shift from a completely different field to tech so I get to know more and grow in the data analytics. Hoping to have a substantial amount of knowledge of SQL as a beginner.
Hi Yemi can we connect I'm also starting a data analysis career....so we could learn together...
@@MinChibuikeOkoli Sure, it would be a pleasure.
Hi Femi, i just came across this video today and going through the comments i saw yours and chibuike’s. I wouldnt mind going the team as i making shift too from a totally different career. Hope you dont mind?
@@cynthiaokechukwu4829 Hi Cynthia, that would be a great idea.
How do we go about connecting? Awaiting Chibuike's reply also.
@@MinChibuikeOkoli Hello Chibuike, how do we connect?
Alex, you are doing a great work. For me, I am kind refresh what I learnt from ATLytiCS boot camp .
Thanks for this all inspiring content. I’m watching from Sierra Leone 🇸🇱.
Thanks for watching!
Even if i have any difficulty understanding what our tutor says, I'm always running to Alex videos, funny enough, he recommended his video for us some days ago😊
I wish I could spend some time with this guy. I would put myself at probably an intermediate skill level with SQL which is one of my main functions in my job... but I have a lot to learn.
This was so informative, thank you CarreerFoundry and Alex!
Man this is amazing and compared to some of the things i did in c++ i can confidently do this! thank you for the reassurance!!!
I am in the middle of the Data Analysis course with Coursera. This video has been a great way for me to further review the SQL portion of the course. Thanks for uploading.
Hello Alex,
I am joining from Lagos,Nigeria.
I am from Louisville Kentucky and I am taking SQL as part of my computer engineering degree
Dear Alex,
thanks for the insight
Thank you for this good information. for Alex 👏
I just watched the replay of this live session, all i can say is thank you Alex.
Hello, I'm from Indonesia. Thank you Alex for making this tutorial. That is very good and easy to understand, this really helped me. 😊
Thanks for the content its a good starter for beginners
This is resourceful. Thank you TEAM
thank you for the video
Thanks for this wonderful tutorial ❤
good work alex work on SQL
I honestly don't why the sudden fascination with data analytics. All I know is, it's getting crazier by the day. But with Alex I'm getting better and better!
Amazing. Thank you
13:23 What was the purpose of the 'AS salary' statement here? I don't quite understand the meaning of 'naming' an output as it is being used here, since 'AVG(salary)' could do the job, maybe?
Awesome work you're doing here, Alex! Thanks!
You don’t have to include the “AS salary”, but it’s good practice to explicitly define the column name when you use a function with “group by”.
If you remove “AS salary” from the query it will still give you the same output, BUT the second column wouldn’t have a name (in SQL Server it would display “No Column Name” for the second column).
Just a side note: In his example, it would’ve improved readability if he used “AS avg_salary” instead.
@@MapleSyrup473 Thanks!
Thank you Alex!
Super awesome. Thank you.
*Dwight Shrute - Assistant to the Lead Baker* pure gold.
Why no time stamps ?
Please update if possible
Great presentation! Is there a link to the slides?
Great job ❤❤❤ thank you
Didnt know Frodo Baggins was born in 2001.
Also, Thanks for the amazing content Alex !
Thanks for the video Alex! Where can I download the dataset to follow the steps? Did I miss this part?
Hello Alex, the content is amazing. Congratulations!
31:13 Could you please recommend some tools to help me to identify the bottlenecks to optimize my queries?
Thank you so much
thank you, Alex , for clearing most of my questions before jumping into the job market. Really enjoyed the whole video.
Keep it Up.
Looking forward to learn SQL
Learning in South Sudan 🇸🇸
Tasos from Australia
thank you for your job!
Thanks Alex.
Nothing can compete Microsoft Excel. It may look not fancy, but superb functionality
will this be only available for a period of time or can i watch the rest another time?
Oliver from Kenya
my name is jaiyeola aminat i love data analysis because anaything can happeng will be abale to solve problem easily eg problem like customer behavior analysis, product performance, financial analyst. etc
from where can i get this data set
Please can I run all these code on PopSQL
My name Njoku Samuel joining from Nigeria. I am intersented in data analytics
I am joining from Pakistan
Love from Pakistan 🙂🙂
thanks
good.from africa
I started programming around 12 years old. I've been a software engineer for 20 years (C# and SQL mainly). In college I had to take Calculus and Statistics to get my CS degree. Waste of time! I've worked and major Banks and Insurance companies. I don't think I've did much above basic algebra. As long as you know the logic the computer will do it for you.
Is this enough for a fresher to enter data analyst field
I really wanted to complete the course. But I use Mac M2. I think I am not having proper guideline about how to setup. I tried through docker and terminal command. It was going okay until my azure studio is not able to find my localhost and could not get connected. I wish I could get a solution of the pretty unknown problem.. :(
Please can I get the sheet to practice as I watch the video
what of statistics?
I really appreciate this video but it has a title that’s not quite right. The only thing that is advanced is window function and there is a very short mention about it.
Is this video enough for data analyst ???!
That's all. I think its more than that.
Interesting
Once we got to join and sbqueries I was sweating. When we got to window functions, I started crying T-T
I really I am Alex videos fun.
is he using SQL Server Managment Studio?
I am Azeez Wahab Oloyede from Nigeria. Want to be a data analyst.
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This SQL video is a waste of time. If any beginner like me in sql has came here to learn sql then please find something else.
part about windows functions is just bad. better skip it
Why are there no fucking captions!!!! 😭
Now, there are closed captions and a transcript. Maybe they just hadn't had time to generate at the time you watched?
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Terrible examples, never ever ever ever use subqueries in WHERE clause
could you do something like this for python too? I'm struggling so much with python...
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