What application scenarios should we consider using mongdb?

MySQL and redis are very easy to use now. Under what circumstances should I abandon these tools and consider using mongo to store data?

In addition:
I am currently exploring the storage of article type data. The style of the article content needs to be saved without destroying the retrieval ability of the content by the retrieval tool. The performance is acceptable. I need a good solution for the database. I will definitely check the information in advance for the characteristics and comparison, so the answer is not simply to compare the characteristics of the database. My actual question may be biased towards actual combat and experience.

I have made an APP backend with millions of daily orders, using Mysql and Redis. MySQL and Redis can support general problems. Is there any reason or scenario that would force or recommend me to use mongo? Mongo’s flexible data type storage, At present, I only think that it is better to use mongo for log storage. I am a newbie in developing article-type websites and need some experience and guidance. Thank you in advance

Reply content:

MySQL and redis are very easy to use now. Under what circumstances should I abandon these tools and consider using mongo to store data?

In addition:
Currently I am exploring the storage of article type data. The style of the article content needs to be saved without destroying the retrieval ability of the content by the retrieval tool. The performance is acceptable. I need a good solution for the database. I will definitely check the information in advance for the characteristics and comparison, so the answer is not simply to compare the characteristics of the database. My actual question may be biased towards actual combat and experience.

I have made an APP backend with millions of daily orders, using Mysql and Redis. MySQL and Redis can support general problems. Is there any reason or scenario that would force or recommend me to use mongo? Mongo’s flexible data type storage, At present, I only think that it is better to use mongo for log storage. I am a newbie in developing article-type websites and need some experience and guidance. Thank you in advance

It’s very difficult to list the appropriate usages one by one...

Let’s think about it in reverse, what scenarios are not suitable for using mangodb?

We have a user personal center:
A user can have many friends, friends can have many messages, messages can have many replies, and messages can have many likes

Use mongodb to model, it is a big json, in which we have a user, and then the user has an array of friends, an array of messages, an array of replies, and an array of like users. These arrays store complete information, which can be queried once Just get them all!

However, it brings a problem
Because the friend information in the friends array is actually user information, storing the complete information results in data redundancy. This problem can be easily solved, that is, store the id in the array, and then correspond based on the id. Check the data in the data source,

However, mongodb does not have a join operation, so you have to manually do the association work in the code layer, which is very...

It seems that mongodb is not suitable for storing data with relationships, relationships, relationships.

Why You Should Never Use MongoDB