* A schema is collection of database objects, including logical structures such as tables, views, sequences, stored procedures, synonyms, indexes, clusters, and database links.

schema是数据库对象的集合，包括表，视图，序列，存储过程，逻辑结构，索引，集群和数据库链接等等逻辑结构。
* A user owns a schema.

一个user拥有一个schema
* A user and a schema have the same name.

user和他的schema的名字相同
* The CREATE USER command creates a user. It also automatically creates a schema for that user.
CREATE　USER命令创建一个user,同时也为这个user创建一个schema
* The CREATE SCHEMA command does not create a “schema” as it implies, it just allows you to create multiple tables and views and perform multiple grants in your own schema in a single transaction.
CREATE SCHEMA命令并不像命令说的那样创建一个SCHEMA, 他只是给你创建table的权限和在同一个事务中在你创建的schema中查看和进行赋与权限的权限。
* For all intents and purposes you can consider a user to be a schema and a schema to be a user.
在任何情况下你都可以把用户和schema当作同一个东西。