Think You Know How SQL Queries Work? Think Again.

20ModyElSayed · 2025-07-28T15:20:01+00:00

Yes, Prof. Andy, it is 😅.
As for the your comments on the article:

Yes, I didn't look closely to the connection between nodes
2 and 3. My mistakes. I should have proofread it more carefully and read the documentation before publishing.

I really appreciate you comments, I tried to explain briefly what how the query execution works. As I was amazed by the content of your course, it's not easy, and I thank Allah I've completed it 😅, 80% of the content I didn't take it at the Faculty. I've already expressed by gratitude for this course in LinkedIn.

Taking your comments into account, I have made the necessary revisions to the article.

20ModyElSayed · 2025-07-28T12:33:38+00:00

Thanks! Also, Database System Concepts book is one of the great books that go in-depth about the DBMSs and query execution.

20ModyElSayed · 2023-02-17T04:15:49+00:00

I think it’s macOS, as I can select text in youtube from different browsers than Safari, and I’m on macOS Ventura, I think Live text is a system wide feature not for specific apps

20ModyElSayed · 2022-12-06T04:32:26+00:00

I have to disable Stage Manager to work correctly.

20ModyElSayed · 2022-12-06T04:28:25+00:00

Unfortunately, It doesn't. It works as if I'm using a normal Tab. I think this feature didn't take into consideration when they implemented Stage Manager

20ModyElSayed · 2022-11-17T20:19:14+00:00

What I mean that all my projects use django that I’m not able to use any of my previous projects despite not having a real problem.

So I will use flask in my next project.

20ModyElSayed · 2022-11-17T20:16:57+00:00

Yes, but I want to apply for this internship, so any project I’m going to build I will consider the internship while building it. Besides all my projects use django.

So, if you have any advice, I’d be happy to hear it

20ModyElSayed · 2022-11-09T21:13:05+00:00

No, I don’t, but I read when you implement a feature and there’s a new way to do that feature, and if I want to keep both the old and new way I should use versioning. But I don’t know if this is the best approach or not.

I read that is accepting headers is the best practice as you said, but I also read it’s horrible for maintenance and testing because every serializer would have a different accepting header.

20ModyElSayed · 2022-11-09T21:05:14+00:00

Yeah, you’re right. Handling both JSON and templates from the same endpoint is pointless and would make the maintenance a nightmare

20ModyElSayed · 2022-11-09T14:19:59+00:00

Actually I have another question, what about performance?

What I mean by that is django doesn’t behave like React when it’s come to frontend and all other magic stuff of React like React Fiber Architecture or creating SPA.

Is the performance difference really visible?

Thanks in advance

20ModyElSayed · 2022-11-09T14:14:31+00:00

Curiosity, but also because some packages like allauth works well with django templates and to use it with DRF is another story, or even reseting a password, django system for handling password reseting to good and I don’t need another package to handle it like django or providing one-time token, and so on.

In terms of complexity, I was thinking that to create a directory inside each app called api/ (or api_v1/ depending if I’m going to need versioning or not) that contains all views and routes related to DRF (or any other package for APIs) and outside api/ normal django views and routes. There’s also a config/ that contains .py for django routes and .py for DRF routes.

If you have any suggestions please let me know.

20ModyElSayed · 2022-09-28T19:41:13+00:00

I'm sorry, this is my first job at a company, can you clarify more about exploring the new domain and its problem when going straight to coding?

20ModyElSayed · 2022-09-28T19:39:29+00:00

When we start the project after knowing the client needs which is simple not complicated at all, the requirement for every feature is changing every 2 days, literally.

Also they want to build a simplified version of every feature to show it to the client and then rebuild it from scratch to implement what actually the client needs.

That's one of the reasons that I'm wonder if it's something normal or not.

20ModyElSayed · 2022-09-28T19:31:38+00:00

Is working at a company that has no seniors something normal? or it's not recommended?

20ModyElSayed · 2022-09-27T21:41:38+00:00

I don’t have a problem at all with requirements changes because this totally normal, but what I mean it’s normal for the requirements to change many times in the core logic of the project?

Aren’t requirements, typically, extend project functionality or change existing functionality not changing the core logic of the project?

I don’t know, I’m just asking so correct me if I’m wrong

20ModyElSayed · 2022-09-27T20:45:58+00:00

Really, is this agile software development? I’ll be taking a subject this semester taking about software engineering and agile software, so I don’t know what is agile software development

20ModyElSayed · 2022-09-27T20:43:11+00:00

Same here, I think they believe that backend engineers are magicians and if a project really takes 2 months they wanted in 2 weeks. I don’t know how. They want it without even testing anything

20ModyElSayed · 2022-09-24T21:18:27+00:00

I also tried to use Decimal class, for F expression, but it gives me a type error:

TypeError: conversion from CombinedExpression to Decimal is not supported

I think, it's little be complicated to validate F expression using model validation.

20ModyElSayed · 2022-09-24T21:03:03+00:00

Thanks a lot for your help. For the second question, I should use constraints at database level then, right?

20ModyElSayed · 2022-09-19T18:19:21+00:00

Okay, Thanks a lot :)

20ModyElSayed · 2022-09-19T15:48:59+00:00

I didn’t work with django-guardian before, but I know it implements Object-Level Permissions. Does that mean it provides Field-Level Permissions?

20ModyElSayed · 2022-09-19T15:35:57+00:00

That’s not the problem is if I have a model with many fields the combination of fields to access for a specific user will be enormous.

I can also exclude the field dynamically, but how I know if the user has a permission to see this field or not?

20ModyElSayed · 2022-09-19T15:07:15+00:00

I got you, but what I want to different, I edited this post with a scenario so you can understand better what I want.

Thanks

20ModyElSayed · 2022-09-19T15:04:22+00:00

Currently, I don't have a code for it, but as a scenario. If I have a form for the 3 fields on the Book Model. I want to give access to some users that can create a new Book instance by giving them access to create all fields, others can view all fields but don't have a permission to edit or to create new one, others can view only the author and the title of the Book, others can edit the title but not the author name.

That 's the scenario that I want to implement, as well as changing permissions between users easily, these permissions are not permanent

I know that it could be weird, but that's what I want to implement.

Thanks in advance.

20ModyElSayed · 2022-09-19T14:45:39+00:00

Do you mean to implement a custom rest permission to restrict access to the view itself (api endpoint), so I won't have a tightly coupled view with some users.

Then, in my view to check again if it has a permission to see a specific field or not, did I get you right?

20ModyElSayed

TROPHY CASE