问题
问答题 简答题
与集中式DBS、分散式DBS相比，分布式DBS有哪些特点？
答案
参考答案：
与集中式DBS相比，分布式DBS中数据库的存储是分布性的，即数据不是存储在同一场地，而是分布存储在多个场地。与分散式DBS相比，分布式DBS中数据库具有"逻辑整体性"，即表面上看，分布式数据的数据库分散在各个场地，但这些数据在逻辑上却是一个整体，如同一个集中式数据库。
搜题请搜索小程序“爱下问搜题”
与集中式DBS、分散式DBS相比，分布式DBS有哪些特点？
参考答案：
与集中式DBS相比，分布式DBS中数据库的存储是分布性的，即数据不是存储在同一场地，而是分布存储在多个场地。与分散式DBS相比，分布式DBS中数据库具有"逻辑整体性"，即表面上看，分布式数据的数据库分散在各个场地，但这些数据在逻辑上却是一个整体，如同一个集中式数据库。
We know that many animals do not stay in one place . Birds, fish and other animals move from one place to another at a certain time. They move for different reasons: most of them move to find food easily, but others move to get away from places that are too crowed. When cold weather comes, many birds move to warmer places to find food. Some fish give birth in warm water and move to cold water to feed. The most famous migration(迁移) of the fish, which is called “salmon(大马哈)”. This fish is born in fresh water but it travels many miles to salt water. There it spends its life. When it is old, it returns to its birthplace in fresh water. Then it gives birth and dies there. In northern Europe, there is a kind of mouse. They leave their mountain homes when they become too crowed. They move down to the low land. Sometimes they move all the way to the seaside, and many of them are killed when they fall into the sea. Recently, scientists have studied the migration of a kind of lobster(龙虾). Every year, when the season of bad weather arrives, the lobsters get into a long line and start to walk across the floor of the ocean. Nobody knows why they do this, and nobody knows where they go. So, sometimes we know why humans and animals move from one place to another, but at others times we don’t. Maybe living things just like to travel.
| ||||||||||