MongoDB Guide (translation) (11)-developer zone-Documentation

Mongodb can be considered a document-oriented database. We are talking about structured documents, not any text documents. You can think of these documents as objects that only contain data, rather than code, methods, or classes. In addition, the association between documents in the mongodb Data Model is less than that between objects in the object-oriented language program.

In mongodb, the document is a conceptual JSON. More specifically, these documents are presented in a format named BSON (representing the binary JSON.

All documents are stored in the collection.

Maximum document size

Mongodb limits the data size of a single BSON object/document. The limit for writing this document is 16 MB.

This restriction is designed as an integrity check; the file size limit is not a technical restriction. This mode may not be ideal if the document size is greater than this. Furthermore, it allows the driver to make assumptions about the maximum file size.

The concept of maximum file size can be used as a limit to ensure that each document does not request more space than the machine RAM space, or request too much network bandwidth to obtain data. For example, it takes 1 second to read a complete MB document over a 1 GB network connection. In this case, the user is limited to one request per second.

Over time, when the computer grows in terms of capacity, this limit will also be adjusted upwards.

Use GridFS when there is a need for large files.