First knowledge of MongoDB

When talking about big data and unstructured data, if you only know Oracle, MSSQL, MySQL, and other relational databases, but do not know anything about non-relational databases such as MongoDB, it seems a little out of sync with the times. In view of this, I began to study MongoDB, in order to solve the storage and retrieval of non-formatted big data.

1. What is MongoDB?
MongoDB is a distributed file storage-based database. Written in C ++. It is designed to provide scalable, high-performance data storage solutions for Web applications.

2. What are the differences between MongoDB and other relational databases?
MongoDB is a product between relational databases and non-relational databases. It has the most abundant functions and features like relational databases.
It supports loose data structures and is similar to the JSON bson format. Therefore, it can store complex data types.

MongoDB does not have the table and row concepts, but has the collection and document definitions. The effect of MongoDB and other relational databases is as follows:

Document
----------> Row
Collection
----------> Table
Database
----------> Database

3. MongoDB features
The biggest feature of Mongo is its powerful query language,
Its syntax is a bit similar to the Object-Oriented Query Language. It can almost implement a vast majority of functions similar to the single-Table query of relational databases, and supports data indexing.

4. MongoDB Retrieval
The MongoDB retrieval method is similar to that of other relational databases, but the syntax is different. In some cases, the retrieval function of MongoDB is more powerful than that of relational databases. Of course, this is also related to the MongoDB storage method.