MongoDB Learning Notes (a) Basic article

1.MongoDB Features

For collection storage, storing data for object types is convenient

Mode free, no need to define any schema (Schma)

Dynamic Query

Full index, containing internal objects

Easy to copy and fail-back

Efficient binary data storage

Support for C # platform drivers

2. Architecture

A single server can create multiple server instances and databases (one instance is recommended for server machines a day),

Database: A series of disk-related physical files (data files, log files, and so on) in MongoDB.

Data Logical Structure: Document (Documnet) collection (collection) database.

Doucumnet: Similar to Row Records in a relational database

Collection: With table types in the database

One MongoDB instance supports multiple databases

Data storage structure:

Each MongoDB database contains an. ns file and multiple data files, and as the table data increases, each reallocation of the data file is twice times the size of the previous data file, with a maximum of 2G per data file.

3. Basic operation

Conditional query: