This is (probably) an artifact of Mongo's schema-less nature; when you don't have tables with structure, every document you store has to detail its own schema inline.
In a relational database, you have columns with names and types, and that info is shared by all of the rows.
In Mongo, every cell has to specify its name and type, even if that layout is shared by every other cell in the document.
Mongo's way is more flexible, but it's terrible for storage efficiency.
In a relational database, you have columns with names and types, and that info is shared by all of the rows.
In Mongo, every cell has to specify its name and type, even if that layout is shared by every other cell in the document.
Mongo's way is more flexible, but it's terrible for storage efficiency.