Oracle

(1) Check the index that needs to be rebuilt Check in the following areas to determine which indexes need to be rebuilt. First, view the user index in the system table space To avoid fragmentation of the data dictionary, try to avoid the presence

First, view the user index in the system table In Oracle, the system table is created automatically when the database is installed, containing all of the database's data dictionaries, the definitions of stored procedures, packages, functions, and

When you use the SQL language to publish a query to the database, Oracle will be accompanied by an "execution plan", which is how the statement will be executed through the data search scenario, through a full table scan, or through an index search.

The following are some of the steps to change, but the startup problem still exists and the person is complete. A single instance database modification SID is simpler, and you can mount the database simply by modifying the pfile related parameters.

Below I have a performance comparison of the concepts of these four partitioning methods, their usage scenarios, and the various partitioning methods. First, the concept 1, Range partitioning This is the most commonly used partitioning method,

1, backup the entire database Backup database format ' C:\rman\all_%U.bak '; 2. Backup table Space Backup tablespace ABC format ' C:\rman\t_%U.bak '; 3, Backup data files 1 backup datafile 5 format ' C:\rman\d_%U.bak '; 2) Backup datafile ' C:\

First, Prepare knowledge: Oracle's logical storage management. Oracle is divided into 4 granularity on logical storage: tablespaces, segments, extents, and blocks. (1) Block: Is the smallest granularity of storage units, now the standard block

The most important component of Oracle SQL uptime is the time spent preparing new SQL statements for execution. However, if you understand the intrinsic mechanism of the executable plan, you can control the time that Oracle spends in assessing the

The original paging query SQL code is as follows: select　ROWNUM　rn,　t.id　ID,　o.name　YYB,u.name　XM,　t.MC　from　tZDYSX t,tuser 　u,lborganization　o　where　t.cjr=u.id　and　u.orgid=o.orgcode　and　t.gx　=　1 order　 by　ID The results are as follows: RN ID

User Management Recovery Oracle Recovery Architecture Ii. Recovery type: instance recovery, media recovery 1, the premise of the recovery of the data files, control files and online logs are not damaged, fully automatic 2, media Recovery: In the

I put it all under the $oracle_home/rdbms/admin, it looks like an ORACLE-provided script $ cat Show_para.sql Col P_name for A40 Col p_description for A50 Col P_value for A30 Set Linesize 10000 SELECT I.KSPPINM P_name, I.ksppdesc P_description,

Whether one or more disks respond to a logical I/O, we all require that I/O be processed at once. Therefore, on the basis of determining the band depth, we need to ensure the stripe bandwidth degree >= I/O request size/stripe depth. In addition,

Session leader and Apps Associates founder, CEO Sridhar Bogelli is based on mass application development advisor, warns Oracle developers should properly use the tools provided by Oracle and Third-party vendors to help them and their companies avoid

First, the question of the proposed Many of the current database applications are client/server patterns developed using Oracle databases. It is well known that using this mode requires the installation of Oracle client software on the terminal.

We typically install the Oracle database on Linux or configure the core parameters of the Linux system when replacing or upgrading the hardware, and then adjust the Oracle system parameters. The actual meaning of these parameters is what, why to

In order to achieve maximum performance, the general database has concurrent mechanism, but the problem is the conflict of data access. To solve this problem, most databases use the method of data locking. Data locking is divided into two methods,

Oracle's sequence is a database object that generates ordered numbers, primarily for automatic generation of primary keys. Without Sequence, the automatic generation of a primary key must be implemented in code logic, which is to get the current

The. NET remote connection Oracle database looks pretty simple, but there are still a lot of problems. Let me share the experience of tossing this thing today. There are many ways to access Oracle database, I use OleDbConnection, this is nothing to

When solving a customer performance problem, come across an interesting SQL statement. First create a test environment: Sql> CREATE TABLE T as SELECT rownum ID, a.* from Dba_objects A, dba_queues B; Table created. sql> ALTER TABLE T ADD

In Rman, we can create a command file that contains the Rman command and then call the file in Rman. Such as: Rman Target Usr/pwd Cmdfile=backup.cmd Alternatively, it can be directly run directly in Rman @ @backup. cmd In addition, RMAN provides