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@Calgary

Answer

kingsw(Steven)
1.primary key, unique key 是不是数据库自动建索引 ?
Oracle automatically creates an index for each UNIQUE or PRIMARY KEY declaration.
2. oracle 允许把 foreign key 建在另一个数据库的一张表的primary/unique key 上吗?
of course
I can't answer this question. Basically, I don't think so.
3. A materialized view is a database object that contains the results of a query.They are local copies of data located remotely, or are used to create summary tables based on aggregations of a table's data. Materialized views, which store data based on remote tables are also, know as snapshots.
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Last Updated: 2006-9-8
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Replies, comments and Discussions:

  • 工作学习 / 专业技术讨论 / 请教一下oracle数据库的几个问题 (估计面试时也会经常碰到) -guoluworker(新高); 2006-9-6 {240} (#3191557@0)
    1. primary key, unique key 是不是数据库自动建索引 ?
    2. oracle 允许把 foreign key 建在另一个数据库的一张表的primary/unique key 上吗?
    也就是说parent/child表不在同一数据库中, 怎么enforce referential integerity ?
    3. 什么是materialized view ?
    • Answer -kingsw(Steven); 2006-9-8 {585} (#3195273@0)
      1.primary key, unique key 是不是数据库自动建索引 ?
      Oracle automatically creates an index for each UNIQUE or PRIMARY KEY declaration.
      2. oracle 允许把 foreign key 建在另一个数据库的一张表的primary/unique key 上吗?
      of course
      I can't answer this question. Basically, I don't think so.
      3. A materialized view is a database object that contains the results of a query.They are local copies of data located remotely, or are used to create summary tables based on aggregations of a table's data. Materialized views, which store data based on remote tables are also, know as snapshots.

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