CS50x 2023 - Lecture 7 - SQL

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This is CS50, Harvard University's introduction to the intellectual enterprises of computer science and the art of programming.

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TABLE OF CONTENTS

00:00:00 - Introduction
00:01:12 - SQL
00:03:01 - Flat-file Databases
00:36:36 - Relational Databases
01:04:46 - Schemas
01:14:21 - Types
01:16:12 - Constraints
01:17:37 - Primary Keys, Foreign Keys, Relationships
01:46:39 - Indexes
01:52:16 - Python and SQL
02:04:24 - Race Conditions
02:13:09 - SQL Injection Attacks
02:19:17 - Little Bobby Tables

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LICENSE

CC BY-NC-SA 4.0
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International Public License

David J. Malan

[shashankkhatri]

I have been in school 14 years now, and I have come across all sorts of professors in India and United States. I have never and unfortunately will never come across a teacher like David Malan. Never have I ever come across a lecture where a question or a doubt comes to my mind and I find the teacher explaining the doubt the next moment in the lecture as I think about it. You read a learner's mind and answer their queries, David. You make the extra effort to ensure that no packets are lost when the knowledge is being transferred to your audience. You have a very special mind and I thank you for existing and making this resource available publicly for free.

[agnesswakio]

Professor David J Malan is the best professor I've ever seen in my life. He makes all the lectures so interesting

[andrewprince]

It honestly pisses me off how underappreciated this class is. Dont get me wrong, people do appreciate it but after taking/watching 3 intro to computer science classes from diffrent schools this is by far the most engaging, interesting, and understandable class I have EVER seen! Im honestly at a loss for words every time I watch another video. The explinations are so indepth, consistant, and interesting that it makes me wish with all my heart that I went to harvard. Good on you guys for making this public. You guys are making the world a better place.

[luilu]

Amazing as always, can’t believe I can actually understand almost all that’s going on. The problem sets to this lecture are my favourite ones so far)

[arborahajdini]

I lost my job last week due to the layoffs that my company did. I have a finance background and I only have job experience in finance. However, I have realized that I like working with data and my plan is to change career and be a data analyst soon. Google analytics course in coursera brought me here. I watched a few minutes from the lecture and I am impressed. It is on my watch list for this week. Thanks👌

[gomojo]

THIS GUY IS AMAZING! I am so appreciative to be learning from him❤

[abielwubet]

i don't know what can I say but this guy changes my Life

[anaswaleed]

It's my favorite lecture.
Thank you, Professor David J Malan.

[Radi_]

Thank you David, that is exactly what I need right now

[arielfayol]

I can't believe a declarative language(SQL) would be so powerful. The hardpart is literally asking the right question.

[chorakdoon]

The way Mr. Malan writes and develops codes in real time step by step gradually improving them is a joy to watch. And it really is easy to see why it is better to change the code that way or what the possible trade-offs from changing codes that way can be.

[kevinpfeffer]

I am new to programing and this is my First course..this teacher is very Good.

[chuhaoliu]

Finally understand how powerful the SQL is. And the final car's picture is very funny!

[enisten]

Wow, the Instagram and refrigereator example at the end was just beautiful :)

[allisonmc]

The first 35 minutes of this lecture would have been very useful for pset 6 haha

[yash]

42:56 .schema shows the CREATE TABLE command that was automatically run by doing import.

[nightspicer]

Completely unrelated to the actual lecture, but "The Office" at 1:39:02 that is Drama rather than Comedy is the original, British show which is assigned both genres.

[edgarhines]

and how that will affect the performance of the database. super useful material, also fixing problems after the fact is no fun

[charlescollinsinaction]

David Malan is a good professor. I hope Harvard is paying him = = +1 according to his knowledge.

[awesomeadvices]

Can i get the csv file? List of favorite languages ?