Andrey Ivanov | Python

2021-09-10 23:46:56 DJANGO ORM OPTIMIZATION #2









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2021-09-10 11:08:52 How decorators can harm the code?

Python provides a huge number of opportunities for decorating functions and classes. However, there is one problem with using decorators - the loss of information of the original function. For example, if we decorate func() using decorator(), we will lose the function name. The fact is that we will use decorator() directly, and func() only internally. Therefore, the code will perceive func.__name__ as 'decorator'. This can be very harmful while we debug the application. We lose the docstring, and the argument list is now replaced with *args, **kwargs. All these things greatly interfere with the development of the application, but you can fix them with the help of functionools.wraps(), which I will tell you about in one of the following posts. Open / Comment

2021-09-09 12:29:22 TELEGRAM TIMER BOT









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2021-09-06 14:52:04 CONTINUE LEARNING REDIS #2









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2021-09-05 09:59:04 MongoDB foreign key

There is no real SQL foreign key in MongoDB. However, we can create it manually. That is, we will point to the ID of some documents, but these IDs will not be checked by the database. But, do we need foreign keys in MongoDB? The fact is that BSON(an addition to JSON) can accept almost any data. For example, if you have an online store with products, and each product has some tags(Italian food, Chinese food, etc.), then these tags can be stored in an array inside our document. This will boost the performance of the queries, since MongoDB will not search for tags in some other collections, but will simply give them in the array of the found document. This approach is very different from standard SQL, where to normalize tables, we need to move all duplicate values to other tables, and then create a foreign key. Open / Comment