Refers to the use of logical backup tool export to export the data structure of the object and to process the data file, Logical recovery is the use of tools when the database object is faulty operations import files using a backup of the database into a database.
Physical backup can also be carried out after closing the open state database in the database, but the backup and restore logic only in the open state.
n Export
Export specific divided into: export table, export programs, export the database in three ways ...
Exporting use exp command to complete, the command common options are:
userid: the export operation for designating a user name, a password, the connection string
tables: a table to specify the export operation
owner: a program designated to perform the export operation
full = y: the export operation is used to specify a database
inctype: used to specify the type of export operation increments
rows: the export operation is used to specify whether or not to export data table
file: used to specify the export file name
n Export Table
(1) export your table
exp userid = username / password @ instance name database tables = (table 1, table 2 ...) file = filename backup path
(2) other aspects of export table
If you want to export the table other programs, you need dba privileges or rights exp_full_database, such system can export tables scott
exp userid = username / password @ instance name database tables = (program names. Table 1 name, program name. table 2 ...) file = filename backup path
Special Note: extension of the backup file is usually .dmp, but this is not necessary.
The command to be executed under dos
Structure (3) deriving table
exp userid = username / password @ instance name database tables = (table 1 ...) file = filename backup path rows = n
(4) using direct way to export
exp userid = username / password @ instance name database tables = (table 1 ...) file = filename backup path direct = y
This embodiment is faster than the default speed in a conventional manner, when the amount of data, using such a method may be considered
Then the character set of the database needs to be fully consistent with the client's character set, otherwise it will error ...
n Export Scheme
Export program is the use of export tool to export all objects (tables, indexes, constraints ...) a program or multiple programs and data, and place the file.
(1) Export own program
exp userid = username / password @ database instance name owner = owner of the file = filename backup path
(2) deriving other aspects
If you want to export to other programs, you need permission or exp_full_database dba privileges, such as system can export any program
exp userid = username / password @ database instance name owner = (1 owner, the owner of the 2 ...) file = path to the backup file name
If the user's permission is large enough, multiple users can be exported at a time schemes, such as system