Oracle数据库的逻辑存储结构主要包括：1、数据块： 最小的存储单位。2、段： 一组具有特定用途的数据块，如表段和索引段。3、区（Extent）： 由连续数据块组成，用于存储特定的段。4、表空间： 数据库中数据的最高逻辑级别，由一个或多个数据文件组成。The logical storage structure of an Oracle database ...
Logical Structure Oracle有一套Logical Structures(逻辑结构),一个Oracle Server只有一个Oracle Database,一个Oracle Database可以由多个Tablespace组成,一个Tablespace可以有多个Segment组成,一个Segmnet可以由多个Extent组成。一个Extent是一组连续的Blocks组成,Block是Oracle中的最小基本单位,Oracle中的Block对应着操作系统...
用于验证特权用户(具有SYSDBA、SYSOPER权限的特殊数据库用户) 二、逻辑数据库结构(Logical database structure) 数据库逻辑结构包含表空间、段、段(extent)、数据块。 1、表空间(Tablespace)
An ORACLE database has both a physical and a logical structure. By separating physical and logical database structure, the physical storage of data can be managed without affecting the access to logical storage structures. Logical Database Structure Logical storage structure = tablespace, segment, ex...
Oracle Server又包含两部分:Oracle Instance和Oracle Database(Oracle Server是一个比较大的概念,我们通常说的Oracle服务器就是指的Oracle Server)。 Oracle Instance(Oracle实例) Oracle Server用于管理数据,数据存储在Oracle Database中,其表现形式为存储在磁盘上的一堆文件,如果要去访问这堆文件,需要有一个媒介---Or...
Incident packages: For the customized approach to uploading diagnostic data to Oracle Support, you first collect the data into an intermediate logical structure called an incident package (package). A package is a collection of metadata that is stored in the ADR and points to diagnostic data ...
In a similar way, the actual tables and columns are logical entities within the physical database. The user who makes a request for data from an Oracle Database probably doesn’t know anything about instances and tablespaces, but does know about the structure of her data, as implemented with...
The database has logical structures and physical structures. Because the physical and logical structures are separate, the physical storage of data can be managed without affecting the access to logical storage structures. The section contains the following topics: Overview of Oracle Grid Architecture ...
Logical data structure – Oracle uses the logical data structure to store data so that you can interact with the database without knowing where the data is stored physically. Partitioning – is a high-performance feature that allows you to divide a large table into different pieces and store ea...
The relational model means that the logical data structures—the data tables, views, and indexes—are separate from the physical storage structures. This separation means that database administrators can manage physical data storage without affecting access to that data as a logical structure. For exa...