Oracle

1. View all table space sizes Select Tablespace_name,sum (bytes)/1024/1024 from Dba_data_files Group BY Tablespace_name; 2. Unused table space size Select Tablespace_name,sum (bytes)/1024/1024 from Dba_free_space Group BY Tablespace_name; 3.

In some cases, you can use the logging mode for the table and index segments, or the mode that does not log logs. If you are using a data pump to import a table segment or index segment, you can Use the nologging mode, and use the data guard or a

Importing imported Oracle Partitioned table data is one of the tasks that Oracle DBAs often complete. Import of partitioned tables exports the same normal table import Export method, but import export need to test Consider zoning specificity, such

--************************************* --Oracle Common Performance View list (10g) --************************************* Advisors Information related to cache advisors V$pga_target_advice V$shared_pool_advice V$pga_target_advice_histogram V$

Data Guard offers two main services: 1 Redo Transport Service: The Primay end of the redo log transmission to one or more standby destinations. 2 Redo Application Service: The redo log which is transmitted from the Primay end is applied to the

CRS provides a number of commands to manage and view the status of the Cluster service, commonly used in Crs_stat, Crs_start, Crs_stop, CRSCTL, etc., which are described in turn. 1, view the status of the cluster The Crs_stat command allows you to

This problem is not only related to parameter shared_servers, dispatchers, but also to server and client Tnsname.ora files. The shared_servers parameter at the DB side controls whether the server can accept share server connections, but the client

One what is the DBWR process DBWR, database write process. The database writer writes modified Blocksfrom the database buffer cache to the datafiles. Oracle database allows amaximum of database writer processes (DBW0-DBW9 and DBWA-DBWJ).

Autoextend extension The physical files of an Oracle database can be set to an automatically growing type, so that when the database needs more space, the physical files are set Automatically grows to the specified maximum value. This has some

1. Definition Package: (1) A collection of related objects that are grouped together, and the package is loaded into memory when any function or stored procedure in the package is invoked. (2) The subroutine access speed of any function or stored

The basic usage of grouping functions is described earlier, and several more advanced uses of group by are described below. 1, rollup in Oracle database with the GROUP BY command, you can provide summary of information functions (similar to

System Checkpoint SCN (V$database (checkpoint_change#)) Data file Checkpoint (V$datafile (checkpoint_change#)) Data file termination SCN (V$datafile (last_change#)) Checkpoints stored in data files Start SCN (V$datafile_header (checkpoint_change#

This seems to be a problem that has been encountered by many people who have installed Oracle RAC (both Linux and Windows). Compatriots with similar experiences call it "the oracle,oui-25031 of the Classics" and the screenshot below. The

V$parameter Oracle parameter modification is more complex, some of the parameters can be modified at the session level, some must be modified at the system level, some parameters are modified immediately after the effective (do not need to reboot),

If an index is not valid for some reason or if an excessive amount of index fragmentation (index Fragment) is caused by a prolonged absence of maintenance, the index fragmentation needs to be eliminated by rebuilding the index. When you need to

Today found an Oracle test library of the set of incorrect character sets, the original character set is UTF-8, the correct character set should be ZHS16GBK, because UTF-8 is a ZHS16GBK superset, can not modify, can only rebuild the database,

The principle of backing up a control file is to back up the control file after the physical structure of the database has changed. 1. Trace: Used to control file rebuilding (generated trace file in Udump) sql> ALTER DATABASE backup Controlfile to

Prior to the dynamic registration of Oracle Listener, static registration is used, the so-called static registration refers to the Oracle instance at startup, read Listener.ora configuration, and then register to listener, which has two main

1, the control document function and characteristic 1 Define the current physical state of the database 2 Maintain data consistency: if the checkpoint in the control file is consistent with the data file, the data is consistent and can be started

In Friday, because the office suddenly power outages, the server restarted, the database did not follow the restart, I found that all the database did not set up automatic restart, in order to prevent future middle server restart, there will be no