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Learn SQL Interactively on Khan Academy

cs-blog.khanacademy.org

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Re: Learn SQL Interactively on Khan Academy

#51

Post by graycat »

jndsn402 wrote: post #50
graycat wrote: post #48

So far my experience is that getting a SQL query correct is fairly easy and usually fun but that the real difficulty, e.g., for SQL Server, is for the rest: (1) Installation. Grim. Barbed wire enema. Wiped out my Windows boot partition requiring that I reinstall everything starting with the Windows DVD. (2) Security. The stuff with users , logins , etc. and nearly everything in SQL Server Management Studio was clear…

If you want to get an understanding of basic SQL without all that overhead, you can try Microsoft Access.

> basic SQL

That was easy. Think of it as close to set theory!

I needed to get through all the overhead stuff since I'm using SQL Server in the server farm for my startup. So, I have code for Web pages with ADO.NET and also some stand alone programs that do SQL Server queries. Again, the only difficult stuff was the overhead stuff, and it would appear that the Khan course would not cover that.

Re: Learn SQL Interactively on Khan Academy

#52

Post by mswen »

rhc2104 wrote: post #46
mswen wrote: post #44

Earlier quoted context omitted.

It was nice to find your site in addition the the Khan Academy's SQL course. Maybe I will try to direct my kids to walk through this. I am curious if you know a resource that would start approximately where your site/tool stops. I know there are books and reference manuals - but I would love to see the intermediate SQL version of your tool - including things like cursors, stored procedures and Common Table Expression…

Hi mswen, Unfortunately, I don't know of interactive tutorials that cover the things you mentioned. The Khan Academy tutorial and SQL Bolt seem to have a few topics not covered by SQL Teaching, so that is a start! (Mainly, write queries) SQL Teaching uses SQLite because that way I don't need to maintain a backend to the site. But if there are more advanced topics that can be taught by SQLite, feel free to make a issu…

I mainly learn now by looking up things when I have a need and then hoping to still remember it 3 months from now when I need it again. The material covered in your tutorial is kind of the daily bread and butter stuff that I use and am comfortable with, but I know just enough to understand that there is this whole other level to SQL querying - even without really dealing with Database Administration and index tuning.

I guess I will just keep learning as the need becomes apparent. Anyway thanks for making your resource available.

Re: Learn SQL Interactively on Khan Academy

#53

Post by pamelafox »

tsumnia wrote: post #35
rhc2104 wrote: post #2

This is great! I created http://sqlteaching.com , so it's wonderful to see Khan Academy's take. If anyone from KA would like to chat with me about SQL tutorials or anything else in general, feel free to reach out- rhc2104@columbia.edu

I love your site and plan to use it as a teaching tool for my Wed Development course I'm teaching. As a request, are you working on a user system to record completed lessons? As an extension, are you looking into making a classroom management system akin to Codecademy? I'd love to create a classroom, have students log in, complete the necessary lessons and have the means to know where they are in the overall plan. If…

Pamela from KA here. We're using the same client-side SQL solution as sqlteaching.com (which is great!). Our editing environment is here and open source: https://github.com/Khan/live-editor

KA does have classroom tools and progress reports, but we don't have the ability for teachers to create their own lessons (if that's what you're looking for). More details on that here: https://www.khanacademy.org/coach-res/reference-for-coaches/...

It's a lot of work to create the classroom management itself (that's done by a whole separate team at KA) so it's not something most folks tack on to teaching sites.

Re: Learn SQL Interactively on Khan Academy

#54

Post by pamelafox »

ivansavz wrote: post #4

Wow, KA hits another one in the outfield! The audio that highlights part of the code is awesome (much better than watching a passive video), and the fact that everything can be executed in real time is awesome. Good job!

Thanks! That environment is all open source, if you're ever looking for some OSS bugs to tackle :-)

https://github.com/Khan/live-editor

Re: Learn SQL Interactively on Khan Academy

#55

Post by peteretep »

schrodinger wrote: post #49
peteretep wrote: post #39

Earlier quoted context omitted.

SQL has almost no practical overlap with set theory. Relational calculus, and relational algebra, sure, but SQL neither operates on nor produces sets.

I've used intersections and unions with sql. And also Cartesian products (a cross join). Don't those count?

No, because in both cases the inputs and outputs are lists, not sets.

Re: Learn SQL Interactively on Khan Academy

#56

Post by ufmace »

graycat wrote: post #48

So far my experience is that getting a SQL query correct is fairly easy and usually fun but that the real difficulty, e.g., for SQL Server, is for the rest: (1) Installation. Grim. Barbed wire enema. Wiped out my Windows boot partition requiring that I reinstall everything starting with the Windows DVD. (2) Security. The stuff with users , logins , etc. and nearly everything in SQL Server Management Studio was clear…

I haven't found that stuff overly difficult so far.

http://downloadsqlserverexpress.com/ is a nice source to install SQL Server and Management Studio from, which also has a link to a blog post kinda mocking how ridiculously hard it is to find the installer on the Microsoft website.

I also find it odd just how long it takes to install, versus Postgresql on Windows installing in like 5 minutes I think.

I'm not sure what you're trying to do with users and permissions, but I haven't had much trouble with that in Management Studio. Add a new login in the server Logins folder, set either a username/password or domain authentication, select databases and set permissions. Not that I've tried anything tricker like assigning multiple users to a role, or doing stuff with AD groups.

https://www.connectionstrings.com/ is a decent resource for connection strings too. It seems to be pretty easy, as long as you're connecting from other Microsoft tools, like Management Studio, sqlcmd, ADO.NET, etc. I'm pretty sure I once spent like a day or so trying to figure out how to get ActiveRecord to connect to SQL Server before I got it working.

That said, the usual lessons could stand to pay more attention to this kind of management stuff.

Re: Learn SQL Interactively on Khan Academy

#57

Post by ufmace »

jndsn402 wrote: post #50
graycat wrote: post #48

So far my experience is that getting a SQL query correct is fairly easy and usually fun but that the real difficulty, e.g., for SQL Server, is for the rest: (1) Installation. Grim. Barbed wire enema. Wiped out my Windows boot partition requiring that I reinstall everything starting with the Windows DVD. (2) Security. The stuff with users , logins , etc. and nearly everything in SQL Server Management Studio was clear…

If you want to get an understanding of basic SQL without all that overhead, you can try Microsoft Access.

Oh god, no more Access. Access has a weird semi-dialect of SQL where it's insanely picky about how you position parenthesis in multiple join statements. I found it impossible to get a query right without the graphical query generator, and that's after routinely writing 5-10 table joins in T-SQL. No thanks, I'd recommend Sqlite over it anyday for a lightweight database. Works great on command line or in any of dozens of helper tools on any platform, and it's Free.

Re: Learn SQL Interactively on Khan Academy

#59

Post by jeffdavis »

This is great... but I am torn because, as someone who has spent a lot of time with databases, I feel like there are many mistakes that can lead to confusion.

First, it's not teaching standard SQL, it appears to be teaching MySQL. That means any user who tries out any other system will immediately run into confusing error messages about the double quotes. Not ideal, and totally unnecessary -- sticking to standard SQL should work reasonably well in MySQL anyway (at the beginner level, at least).

Second, in the section "Creating Tables and Inserting Data", the teacher jumps into surrogate keys immediately. Again, I feel that is unnecessary and will just lead to confusion. The beauty of a relational database is that it connects with the real world; and having arbitrary numbers floating around destroys that beauty.

I really hate to criticize, because I really support the effort. Hopefully my feedback is useful.

Re: Learn SQL Interactively on Khan Academy

#60

Post by rhc2104 »

jeffdavis wrote: post #59

This is great... but I am torn because, as someone who has spent a lot of time with databases, I feel like there are many mistakes that can lead to confusion. First, it's not teaching standard SQL, it appears to be teaching MySQL. That means any user who tries out any other system will immediately run into confusing error messages about the double quotes. Not ideal, and totally unnecessary -- sticking to standard SQL…

Khan Academy is using SQLite (because there is a JavaScript version of it)
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