There are two types of databases, relational and non-relational.

Databases, in short, can be regarded as electronic filing cabinets - places where electronic files are stored and users can add, intercept, update, delete and other operations on the data in the files.

Relational databases include:

Oracle, DB2, Microsoft SQL Server, Microsoft Access, MySQL and so on.

Non-relational databases include:

NoSql, Cloudant, MongoDb, redis, HBase, and so on.

Extended information:

Advantages of non-relational databases:

1, high performance: NOSQL is based on key-value pairs, which can be imagined as a correspondence between the primary key and the value in a table, and does not need to go through the SQL layer of parsing, so the performance is very high.

2, good scalability: again, because it is based on key-value pairs, there is no coupling between the data, so it is very easy to expand horizontally.

The advantages of relational databases:

1, can be complex queries: you can use SQL statements to facilitate in a table as well as a number of tables to do very complex data queries.

2, transaction support is good: so that for high security data access requirements can be realized.

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