ORACLE 11G Learn from scratch-20141208

1.3.6, Duan

Used to store all data of an object in a table space with an isolated storage structure, which consists of one or more zones.

1. Data segment

Used to store all the data in the table.

2. Index segment

All data used to store the index.

3. Temporary section

Used to store temporary data resulting from a sort operation.

4. Rollback section

Used to store the value of the user's data before being modified so that the user's modifications to the data are rolled back under certain conditions.

1.3.7, District

A block of physically contiguous storage. is the smallest unit of storage allocation, consisting of one or more blocks, with one or more extents forming segments.

1.3.8, data block

The smallest data management unit, and the smallest unit for performing input and output operations. The minimum unit of operating system execution input and output operations is the operating system block.

Components:

1. Block Head: Attribute information, such as the physical address of the block, the type of segment to which the block belongs, and so on.

2. Table directory: If the data stored in the block is a table data, the table directory stores information about the table.

3, Row directory

4, free space:

5. Row space: The storage space already used in the block, which stores the data of the table or index in the row space.

1.4. New features of Oracle 11g

1.4.1, database Management Section

1. Program Management

Allows a user to fix a query plan for a particular statement, with no statistical data changes or changes to the database version, without altering the user's query plan.

2. Resource Manager

Manage CPUs, manage I/O. Set priority, file type, and ASM disk groups for a specific file

3, access to the suggestion device

4. Replay of the database

Captures the load of the entire database, and passes it to a test database created from a backup or standby database, and can then be tuned by replaying the test system.

5. Event Packaging Service

6. Automatic SQL optimization

7. Backup and Recovery of database

8. Automatic Diagnosis Knowledge Base

9. Automatic Memory optimization

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ORACLE 11G Learn from scratch-20141208