Advanced SQL Tutorial | Subqueries

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  • Опубликовано: 26 ноя 2024

Комментарии • 223

  • @adityapandey6969
    @adityapandey6969 Год назад +77

    The entire, Beginner, Intermediate, and Advanced playlists are a gold mine, Alex!
    Thank You!!!

  • @ekinci_io
    @ekinci_io 8 месяцев назад +4

    As someone who received SQL training during master's degree, I have to say that I learned much more from Alex's SQL lessons than what I learned at school. You are amazing Alex!

  • @halildurmaz7827
    @halildurmaz7827 2 года назад +5

    Perfectly clear explanation. However, I also noticed wrong information:
    7:17 You said, "In your Subquery, you can only have 1 column selected". However, you can select multiple columns by using parentheses --------> WHERE (a, b) IN (SELECT a, b FROM x)

  • @usuallyclueless4477
    @usuallyclueless4477 3 года назад +188

    I have a Coursera certificate in MySQL, but you've explained it so much better than the instructor of that course.

    • @ericfiumano4694
      @ericfiumano4694 2 года назад +15

      I cannot speak for MySQL course cause I haven't attended it but, having attended other technical Coursera (and Google, too) Courses I fet a little bit disappointed regarding the content. Definitively, too much bla bla bla and little practical approach.

    • @wasitthat
      @wasitthat 2 года назад +6

      I'm taking that course right now. Have to heavily supplement it with the mode tutorial because the actual course lacks soooo much detail and examples!

    • @tasadem20
      @tasadem20 2 года назад +9

      Same. Taking a 4 week class from Coursera and i was stuck on week 3 where the instuctor teaches subquiries and joins. Hope this video will help

    • @ninas.2724
      @ninas.2724 2 года назад +4

      @@tasadem20 I’m having the same problem in week 3, I couldn’t understand the instructor and she didn’t not explain correctly

    • @HortenseEagle
      @HortenseEagle 2 года назад

      I have the same issue on datacamp, before I realised I was already doing nested subqueries and CTEs 💀

  • @damasusaditama2148
    @damasusaditama2148 3 года назад +84

    All your SQL tutorial videos from the basic up to this have helped me understand SQL, MUCH BETTER compared to the explanation that I've got from a bootcamp. Your explanation is so complete and concise. Thank you so much, Alex!

    • @AlexTheAnalyst
      @AlexTheAnalyst  3 года назад +3

      Really glad to hear it! :D

    • @alexter001122
      @alexter001122 Год назад

      Question: were you able to land an analyst job after finishing your bootcamp?

    • @damasusaditama2148
      @damasusaditama2148 Год назад +3

      @@alexter001122 yes. I finished my bootcamp in Sep-2021, then applied for a data analyst position at various startups, did some interviews, and started working as a data analyst in Feb-2022.

  • @ninahbae2922
    @ninahbae2922 Год назад +14

    Today i have completed SQL😩😩🥰❤️ Am so grateful for having found your channel, i believe by 2024 i will land a data analyst role in government or health care all studying from this bootcamp from scratch🙏🙏🙏 never been as committed, thank you so much once again, tomorrow am starting off with Python

    • @ngunyi101
      @ngunyi101 Год назад +2

      wish you all the best in your journey. consistency is key 💪

    • @mizerosamuel5613
      @mizerosamuel5613 8 месяцев назад

      How is it now????

  • @marcellaperkes4870
    @marcellaperkes4870 2 года назад +24

    Thank you Alex! 🙌 For the last year I’ve been learning about data analysis/computer science part time, with the goal to move into the tech industry so that I can WFH, be available to my kids, and have income growth potential. Your videos were fundamental to my learning. I just landed my first job in the industry, and I attribute a big part of that to you.

    • @IceTobSmoKeo
      @IceTobSmoKeo Год назад

      How was your journey now? Mind sharing us your experience?

  • @ThiagoSimoes79
    @ThiagoSimoes79 Год назад +4

    I thought I knew SQL, but this whole series of videos help me understand that I don't know anything. Although your explanation was ease to follow and understand, I feel that need more study to really understand all the concepts.Thanks a lot for your time to make this series.

  • @davidcorona644
    @davidcorona644 Год назад +1

    Holy mackerel! We think and code exactly the same.This is exactly how I teach people about sub-queries, and partition by, and even the rarely used 'right join' which is similar to 'not in' where clause sub-query.

  • @stultuses
    @stultuses 2 года назад +3

    Excellent, someone who knows how to zoom in for those watching on mobile!!!!

  • @jjsinclair94
    @jjsinclair94 3 года назад +34

    This has come just in time for an interview I have in the morning for a modelling analyst position, can't begin to describe how much your videos have helped! Keep up the crazy good work you are doing here!

    • @nnaemekaonwuka7474
      @nnaemekaonwuka7474 3 года назад +2

      best of luck and i hope you celebrate with us when you get it. cheers

    • @rosslobo
      @rosslobo 2 года назад +2

      did you get that job ?

  • @loose.electricity
    @loose.electricity Год назад +6

    Just finished this series, thank you so much, you've re-ignited my passion for learning again. These simple, clear explanations of concepts has given me the confidence to dive back into more advanced concepts again.

  • @flyeagle320
    @flyeagle320 2 года назад +2

    I Am glad I followed the whole series of SQL tutorials from easy to advanced. Now I am clear on the concept. Now I am going to follow a real-world project of yours.

  • @yanirhaim7787
    @yanirhaim7787 3 года назад +6

    Thanks for the great tutorial! Currently on my Google Data Analytics Certificate! This video made it easier to understand the concept!

  • @melissaleigh3013
    @melissaleigh3013 Год назад +2

    King, you are the best sql teacher on youtube. Thanks SO much for making content on sql concepts that are actually used in everyday work flows.

  • @ColonelHathi
    @ColonelHathi 10 месяцев назад

    I just finished the Beginner, Intermediate, and Advanced SQL videos. Thank you, Alex, for publishing these. I'm adding SQL to my tool belt. These were a fantastic first look at the language.

  • @Alexdasilva872
    @Alexdasilva872 Год назад +5

    I've just finished this series (1 week). I'm going to rewatch it all again (hopefully 1 day) and then start the Portfolio Project. I started from 0 and your videos are purely useful content, it made me understand SQL really fast.
    Thanks from Spain.
    PD: I will communicate here when I finish the course completly and also if I am lucky enough to get a job.

  • @matheuspegorari1094
    @matheuspegorari1094 3 года назад +7

    I love your videos, content is never enough. I know sometimes may be obvious to talk about something like subqueries when we have lots of content in the internet, but your explanation is very pertinent and very didatic, i learned a lot today. For this I thank you.

    • @AlexTheAnalyst
      @AlexTheAnalyst  3 года назад +1

      So glad to hear that! And I agree - sometimes one good explanation of something is all you need to really get the grasp of it

    • @esthernwaogu592
      @esthernwaogu592 Год назад

      Hello matheus please can we chat on telegram I need assistance

  • @sols9019
    @sols9019 8 месяцев назад +1

    Done for SQL Tutorial after 3 weeks of learning and spending 2-3 hours in each session while creating different scenarios outside the samples. hehe Mygee! I made it! haha! Thank you Alex! Next step is to get a certificate of SQL before proceeding to the other Tools. Hopefully I'm doing it right. Lol

  • @akj3388
    @akj3388 2 года назад +2

    Thanks for letting us know that for a subquery in the SELECT and WHERE clauses; it can only have a single value and single column respectively as an output.

  • @DiwasSapkota-x3q
    @DiwasSapkota-x3q Год назад +1

    Thanks Alex for teaching Advance SQL REALLY QUICK.

  • @ImEli2215
    @ImEli2215 Год назад

    After roaming around with other tutorials, it makes your tutorial more valued. Thanks sir

  • @charlesrobertson1860
    @charlesrobertson1860 Год назад +1

    Thanks so much for these tutorials! I had a basic understanding of queries in ArcMap for GIS data and didn't understand why it was really that important but now thinking of it as having a database that has pre-made queries that can be manipulated in different ways to process and analyze data has made me understand its importance!

  • @yingdeng1106
    @yingdeng1106 2 года назад +2

    Thank you so much Alex! I went through the basic, intermediate and advanced SQL Tutorials. I would love to learn more about the store procedures in detail!

    • @AlexTheAnalyst
      @AlexTheAnalyst  2 года назад +1

      You're most welcome! Thanks for learning with me :)

  • @bryanpaulcardinoza7693
    @bryanpaulcardinoza7693 Год назад

    Just finished watching all sql tutorial videos in this bootcamp. Time to watch the portfolio project.

  • @AlijandroI
    @AlijandroI Год назад +1

    Had troubles understanding some concepts from a bootcamp but your explanations are amazing! Concise, precise and easy to understand.Thank you!

  • @ivorkoruznjakk1579
    @ivorkoruznjakk1579 2 года назад

    Im taking a test today and this is the perfect video for a quick reminder of everything.

  • @salikmalik7631
    @salikmalik7631 3 года назад +14

    Your videos are good Alex.
    We need a playlist of SQL needed for data science. Its a request. :)

  • @syaoransakura8839
    @syaoransakura8839 3 года назад +1

    Finally finish this advanced tutorial. Keep going for next series...

  • @JohnRussell9
    @JohnRussell9 2 года назад

    Thanks for giving such a clear and concise explanation for why one would use subqueries! I'm currently working through the Google Data Analyst certification program and your explanation and approach was much easier to understand than the instructor who presented on this very topic.

  • @salehgamal1511
    @salehgamal1511 2 года назад

    I have taken udacity course on sql and i applied the course on an actual db but your tutorials are much better realy specially on the joins

  • @ezhankhan1035
    @ezhankhan1035 11 месяцев назад

    Brilliant SQL Tutorial Series! Every Video has really helped to fill in any potential gaps in my knowledge and even reinforce my existing skills. Thanks Alex!

  • @momohtimothy6898
    @momohtimothy6898 8 месяцев назад

    I am Finally done with SQL on this amazing channel. But got to go back for some revisions.

  • @AnglBunny
    @AnglBunny Год назад

    Thank you so much for posting this series. I am learning SQL for the first time and your videos are extremely helpful :)

  • @fantasytrain42
    @fantasytrain42 Год назад

    I have enjoyed your videos. I have been programming and working as a dba for a long time, 28 years - since sql server 4.2. (Do you remember *=). I would consider myself an expert in sql server. I was even able to pick up a couple things in your sql videos that I didn’t know or at least did 8n a different way. Great job. Looking forward to the python and newer content. Working towards learning how to use ML to help clean data and find errors over the next year.

  • @tomilolaomowumi7156
    @tomilolaomowumi7156 2 года назад

    You posted a tutorial on CTE before this. I am following from the older videos to the newer ones so I got lost for a bit and had to come find this. Thank you for making learning easy

  • @gianniprocida3332
    @gianniprocida3332 2 года назад

    Very helpful. All your videos about SQL are very easy to grasp and concise. Thank you so much.

  • @louisizuchi1626
    @louisizuchi1626 2 года назад +1

    Thank you Alex, i really learnt a lot from the beginners series up this advance series

  • @vuphan2956
    @vuphan2956 3 месяца назад

    This is a great video about subquery. Thank you, Alex!

  • @thesamshekhawat9500
    @thesamshekhawat9500 Год назад

    Thank you so much Alex for providing such a valuable skills for free. It really made me become a aspiring data analyst.

  • @1689JeffChavez
    @1689JeffChavez Год назад

    On my journey through the boot camp...
    This comes in handy. Thank you.

  • @richardogden1466
    @richardogden1466 Год назад

    Thank you for your work and detailed explanations Alex. I mainly use COGNOS and COGNOS SQL so this is a great crash course for me to learn the differences between the two.

  • @linavilaa
    @linavilaa 2 года назад

    I learned so much with your videos. You made learning SQL very fun. I enjoyed your examples. Thank you!

  • @JustinLietz
    @JustinLietz 6 месяцев назад

    Thank you for sharing, really really appreciate this. I would love to see more advanced stuff, specifically examples where you're using synonyms across different servers within source stored procedures (used to populate stage tables) to make joins along with ctes. I am at an internship right now, and still in my first year of college, I feel completely lost when working in these health insurance databases, most videos on youtube don't really go into more complicated stuff that I work with everyday so thank you again
    Many of these queries in the code base are 3000+ lines long and my brain goes numb looking at all the subqueries, joins, and obscure functions I have no idea what they do

  • @icantw8
    @icantw8 2 года назад

    This is tremendously helpful. Got to resolve a blocker because of you. Thanks!

  • @MrXRes
    @MrXRes Год назад

    You just basically saved my career now

  • @csyronnegalang679
    @csyronnegalang679 7 месяцев назад

    Hi! I just tried the syntax for subquery in where but I tried it also using join and got exact result
    *Alex subquery in Where*
    select EmployeeID, JobTitle, Salary
    from EmployeeSalary
    where EmployeeID in (
    select EmployeeID
    from EmployeeDemographics
    where Age > 30
    )
    *my syntax*:
    select demo.EmployeeID, JobTitle, Salary
    from EmployeeDemographics as demo
    join EmployeeSalary as sal
    on demo.EmployeeID = sal.EmployeeID
    where Age > 30
    Anyway, I find your tutorial very informative and tried to use some work arounds if they will have the same output. Thank you always, Alex!

  • @cmhanft
    @cmhanft 3 года назад

    God bless you, Mr. SQL.

  • @itsReshad
    @itsReshad 2 года назад +1

    Keep up the Amazing content Alex!

  • @lefamokgatle2489
    @lefamokgatle2489 2 года назад

    Thank you so much. I had trouble understanding sub-queries. You've explained it so well. 😎

  • @StephanieBassil
    @StephanieBassil 2 года назад +2

    Thank you Alex for ur way in simplifying the training! Are you giving later more advanced videos about SQL or that is all ?

  • @itikalaneelu9126
    @itikalaneelu9126 Год назад

    keep up the good work sir. I have been following your videos and techtfq videos as well and learned so much

  • @Joi_SS
    @Joi_SS 3 года назад +5

    I just learned this recently! Wonder do you have any recommendation for an intermediate level courses after the beginner course? I'm 75% done with my SQL beginner course. Thanks! :)

  • @jayashukla4799
    @jayashukla4799 2 года назад +1

    WOAHH!!!😍😍 Thank you so much for making it easy :)

  • @tausifahmed4760
    @tausifahmed4760 3 года назад +3

    Hey Alex thanks for making videos which are so informative and helpful..as a mechanical engineer who wants to change his profession to data analyst ..what will u suggest to learn first

  • @iskate248
    @iskate248 2 года назад

    Sounds like Dane Cook is teaching me SQL. Good video, thank you.

  • @michaeloyetunde8974
    @michaeloyetunde8974 Год назад

    Thank you so much, Alex. Your videos are superb.

  • @YoYo-gf9wb
    @YoYo-gf9wb 3 года назад +1

    You should remind ppl to like your videos. I really like all your videos, super helpful~~~ but always forget to like it....

  • @A7mouzi
    @A7mouzi 5 месяцев назад

    do you have any suggestions on where I could practice these functions more? and this playlist is really beneficial thanks for the time and effort!

  • @SeanBaker
    @SeanBaker 3 года назад +12

    I’ve been using SQL on my job since 2007, and I swear that I still don’t know everything I should know when it comes to really "complicated" queries.

  • @jonathanbrotto7278
    @jonathanbrotto7278 2 года назад +2

    I wish I had this during my undergrad over a decade ago.

  • @marklabaclado2176
    @marklabaclado2176 Год назад +1

    What program is used here? It looks like a Jupyter NB for SQL

  • @jpzhang8290
    @jpzhang8290 Год назад

    Subquery can also alternatively be replaced by temp table or CTE.

  • @rickydethan7037
    @rickydethan7037 Год назад

    I just finished the SQL tutorial from beginner to advanced. Now I want to start the portofolio project but part 2 & 4 of that video are missing. Let me know when those video already uploaded. thank you very much and sorry if there's something wrong about this comment, I'm still learning English

  • @stylewithsmriti
    @stylewithsmriti 2 года назад

    Please make a video on Window Functions. I love your videos :)

  • @kristinaannabel7113
    @kristinaannabel7113 Год назад +1

    that was really quick

  • @anthonynkem
    @anthonynkem 2 года назад

    Thanks Alex.
    Great course

  • @pipertripp
    @pipertripp 10 месяцев назад

    This looks like a really interesting subject. I didn’t know anything about it until now, but I suspect the exponential, geometric, and weibull distributions might factor in?

  • @massimoriggio6297
    @massimoriggio6297 3 года назад +1

    Hello Alex, why did you create the subquery when to get the average you could have just specified :
    "SELECT EmployeeID, Salary, (AVG)salary
    FROM EmployeeSalary"?
    I am really confused and would be glad if you could help.

  • @MaheenAbdulwaheed
    @MaheenAbdulwaheed Год назад

    Hey Alex! All your videos on Sql Tutorials are awesome! Can you make a video on how to use primary and foreign keys in Sql Server? You've mentioned in one of your videos that you'll be covering those topics but I haven't come across the PK and FK in the Sql Tutorials(maybe I've missed them). Or if you have a video already out, could you direct me to it? Thanks for all the videos, they've helped me understand SQL Server much better!

  • @abhisquest
    @abhisquest 3 года назад +3

    Hello Alex,
    Where can we find some practice excercises to practice SQL queries?

    • @AlexTheAnalyst
      @AlexTheAnalyst  3 года назад +3

      Try StrataScratch.com or Leetcode.com :)

    • @abhisquest
      @abhisquest 3 года назад

      @@AlexTheAnalyst Thank You 🙂

  • @shappirefishing1186
    @shappirefishing1186 Год назад

    Excellent Tutorial

  • @BestInTheWorld215
    @BestInTheWorld215 2 года назад +1

    I'd love a tutorial for working with SSIS Packages

  • @mfundohg958
    @mfundohg958 2 года назад

    Thank you this series is really helpful. 👌

  • @ves5657
    @ves5657 2 года назад +1

    What happens if you remove "over ()" from the "with Partition By" example?

  • @veronicab2096
    @veronicab2096 3 года назад +2

    In the last query, you used a subquery in the WHERE clause to filter for employees over 30. Could you also have accomplished that by joining the two tables and adding a WHERE EmployeeDemographics.Age > 30?

    • @janiobachmann5029
      @janiobachmann5029 3 года назад

      Agree Veronica, in that case we could use it in a join table. However, I believe using the subquery in the where clause is much faster than joining in this case. Maybe Alex could confirm that?

  • @marius9897
    @marius9897 Год назад

    Hi Alex. Thank you very much for this series of videos. For me, your method of teaching is easy to follow and understand. Are perhaps you going to produce a tutorial on Goolge's Looker too in the near future?

  • @queensam6868
    @queensam6868 Год назад +1

    Great content

  • @Charlay_Charlay
    @Charlay_Charlay Год назад +1

    Thanks Alex!

  • @pramudyadika_
    @pramudyadika_ 2 года назад +1

    thank you Alex!

  • @Anipro88
    @Anipro88 2 года назад

    Very helpful, thank you. Is there a way to find out the input parameters of a stored procedure, that someone else may have created, w/o using the "modify" option?

  • @romanvasiura6705
    @romanvasiura6705 2 года назад

    Thank you for this video and recommendation

  • @RodStremel
    @RodStremel 3 года назад +5

    Your content is awesome, Alex! Thanks for all the videos! I don't know if you've answered this before, but I need to ask: how can I show my SQL skills in a portfolio project? Showing Python code with all the EDA and data viz is ok, I can do it, but I always have a hard time figuring out how to show employers that I know SQL (it seems like all they care about is if I've used in a job situation, which I haven't had the chance to). Any tips on that? Thanks again!

    • @Magmatic91
      @Magmatic91 3 года назад

      It's a good question. I'm kind of in the same situation than you. Personally, what I'm trying to do is simply looking for datasets online then trying to make my own project. You can for example find free datasets in SQL server website or Kaggle but I agree with you that it's not that simple. Hopefully Alex will answer this comment.

  • @mouradserrai6762
    @mouradserrai6762 Год назад

    UPDATE youtube
    SET button_Name = 'star_rating'
    WHERE button_Name = 'like'
    here we go @Alex you have got my 5 stars ;)

  • @slimisslow244
    @slimisslow244 2 года назад +1

    Hi there! great content!! Just to know, in a working place, how often is a subquery used compared to the join function?
    As both can give the same result.

    • @AlexTheAnalyst
      @AlexTheAnalyst  2 года назад +3

      Joins are used all the time - subqueries about 10% as many times as joins

  • @natekennedy1668
    @natekennedy1668 3 года назад

    SELECT * FROM (SELECT employeeID, Salary, AVG(Salary) AS Allavgsalary FROM EmployeeSalary); CAPS LOCK IS FRIEND NOT FOOD

  • @esthernwaogu592
    @esthernwaogu592 Год назад

    Hello Alex
    I love ur videos they v been guiding me through data analysis but i v issues with my sql

  • @davekoot7880
    @davekoot7880 Год назад

    Thanks for the video! Studying SQL with DataCamp but the explanation on subqueries is very short..

  • @syedalinemath917
    @syedalinemath917 Год назад

    Thanks it was helpful!

  • @salikmalik7631
    @salikmalik7631 3 года назад +1

    And one thing I am confusing in, that which one is better to learn Tableau or Power Bi?

    • @KrackaLaka
      @KrackaLaka 3 года назад

      wondering the same thing

  • @lucatintor4896
    @lucatintor4896 Год назад

    Hello teacher where can I load those data to practice following your explanations?
    Thank you

  •  Год назад

    Hi Alex! I'm following you in LinkedIn. Pls, keep me post it about the data analyst bootcamp you plan to launch. I, myself I am changing career. I want to be more technical marketer with strong focus on web analytics and touching here and there analytics subjects....

  • @אוריתגנה
    @אוריתגנה Год назад

    hello Alex and thanks for greate videos.
    What "over ()" means?
    thanks

  • @ChilledSquirrelyt
    @ChilledSquirrelyt Год назад

    Where is primary and foreign key video could you please share the link

  • @DeepakBhargav-or8rs
    @DeepakBhargav-or8rs 7 месяцев назад

    thank you so much for this tutorial

  • @janetbartonjo8916
    @janetbartonjo8916 2 года назад

    Hey,i love your videos! I have a question though. In your last example you can simply do the normal query and filter using "WHERE Age>30" and still get the same results, right? If yes,then why do we need to use WHERE sub query?

  • @robinchriqui2407
    @robinchriqui2407 3 года назад +2

    Hi Alex thank you for your work great tutorial. Today I had a test in SQL for a company it was so hard. Do you know a good platform to train myself with exercice ? I mess this interview but I really would to do better next tile

    • @AlexTheAnalyst
      @AlexTheAnalyst  3 года назад +1

      Try Leetcode or Stratascratch - both are good options

    • @fabio336ful
      @fabio336ful 3 года назад +1

      You can use HackerRank too. Its free

  • @frybait0626
    @frybait0626 Год назад

    How about doing an AVG SALARY for each employee instead of AVG FOR ALL? How do you query that?

  • @claraoliva254
    @claraoliva254 11 месяцев назад

    Just to clarify, only the where statement combined with the subquery can only have 1 column selected? SELECT and FROM can select all columns if wanted from a subquery? thanks!

  • @ishantjain1
    @ishantjain1 3 года назад

    ​ @Alex The Analyst Hey alex can you explain the functions CUME_DIST(),FIRST_VALUE,LAST_VALUE,RANK,DENSE_RANK,LAG,LEAD,NTILE etc (window functions)