Database Schema Design Overview
This document provides the basics of MatrixOne database schema design. This document introduces terminology related to MatrixOne databases and subsequent data read and write examples.
Key concept in MatrixOne
Database Schema: The database schema mentioned in this article is the same as the logical object database. It is the same as MySQL.
A database in MatrixOne is a collection of objects such as tables.
To view the default database contained by MatrixOne, ues
SHOW DATABASES; statment.
To create a new database, ues
CREATE DATABASE database_name; statement.
A table is a collection of related data in a database.
Each table consists of rows and columns. Each value in a row belongs to a specific column. Each column allows only a single data type. To further qualify columns, you can add some constraints.
Other supported logical objects
MatrixOne supports the following logical objects at the same level as table:
View: a view acts as a virtual table, whose schema is defined by the SELECT statement that creates the view.
Temporary table: a table whose data is not persistent.
MatrixOne supports both user-based and role-based access control. To allow users to view, modify, or delete data, for more information, see Access control in MatrixOne.
Limitations on identifier length
|Identifier type||Maximum length (number of characters allowed)|
Limitations on a single table
|Type||Upper limit (default value)|
|Columns||Defaults to 1017 and can be adjusted up to 4096|
|Size of a single line||6 MB by default|
|Size of a single column||6 MB|
Limitations on data types
For more information on data types, see Data Types.
Number of rows
MatrixOne supports an unlimited number of rows by adding nodes to the cluster.