Oracle

1. Enterprise Manager has two forms: Database Control and grid control. Database control is used to manage a single database, and grid control is used to manage multiple databases. Database Control is generally configured by dbca during database

To update multiple rows: There are many steps, but the efficiency is relatively high:1. Create Table temporary table value (select a. ID, A. Name, B. Name,... from Table1 A, Table2 B where a. ID = B. ID)2. delete records in Table 1. Do not drop3.

1. automatic Installation selected during installation. Because the user name and password have been forgotten for a long time, I have tried several default user names and passwords (The table contains the default user name and password ), the user

Oracle intelligent agent executable encounters a problem  Recently, I just installed Oracle 9i on the system and found that the computer name was not changed after the installation. After I changed the name, every time I started the system, the

Official Website description Owid: a globally unique address for a row in a database.   Rowid can be divided into extended rowid and restricted rowied.   1.1 restricted rowid Internally, the rowid is a structure that holds information that the

The types of Oracle Data Dictionary views are: User, all, and DBA. User _ *: Information about objects owned by users, that is, information about objects created by users All _ *: Information about objects accessible to users, that is, information

Rollup is an extension of group by, which performs subtotal and total operations. cube contains rollup, which is a more granular subtotal and total. When there is only one field, rollup and CuBE are the same. You can use grouping to test rollup and

Dbms_stats can effectively estimate the statistical data (especially for large partition tables), obtain better statistical results, and finally develop a faster SQL Execution Plan.Exec dbms_stats.gather_schema_stats (Ownname => 'Scott ',Options => '

After the computer name is changed, all Oracle services cannot be started.We recommend that you do not modify the computer name at will, because it is troublesome to modify many Oracle configurations after you modify the computer name. My original

In modern multi-user multi-task systems, it is inevitable that multiple users access a shared object simultaneously. This object may be a table, row, or memory structure, to solve the data security, integrity, and consistency problems caused by

Routine Management and Maintenance Enable and disable the start and stop ggsci commands, view the status using the info and status commands, and view the statistics using the stats command, check the discard file and other log files (for example,

The SQL code is as follows:   Create or replace procedure procsendemail (p_txt varchar2, p_sub varchar2, p_sendor varchar2, p_receiver varchar2, p_server varchar2, p_port number default 25, p_need_smtp int default 0, p_user varchar2 default null, p_

  SQL statement: /* Formatted on 14:51:13 (qp5 v5.185.11230.41888) */select D. tablespace_name, space | 'M' "sum_space (m)", blocks "sum_blocks", space-nvl (free_space, 0) | 'M' "used_space (m )", round (1-nvl (free_space, 0)/space) * 100, 2) | '%'

   1. Enhanced add column description In Oracle 11gr1, Oracle enhanced the Add column. Instructions on the official website: Http://docs.oracle.com/cd/B28359_01/server.111/b28279/chapter1.htm#NEWFTCH1  1.1 Enhanced add column functionality Default

Oracle Lock Mechanism   A database is a shared resource used by multiple users. When multiple users access data concurrently, multiple transactions can access the same data simultaneously in the database. If concurrent operations are not controlled,

  Sometimes we see the following information in AWR:     The corresponding three SQL statements are as follows: (1) Call dbms_space.auto_space_advisor_job_proc () (2) calldbms_stats.gather_database_stats_job_proc () (3) Insert into WRI $ _

In AWR, we may see the following information:     Here, the read byother session takes a lot of time.   Read by other session is described as follows: When informationis requested from the database, Oracle will first read the data from disk beyond

  Installing Oracle 10.2.0.1 on Oracle Linux 6.1 is a tortuous process when installing software. When dbca creates an instance, it encounters: ORA-27125: Unable to create shared memory segment   The installation is interrupted. Rac2:/u02> oerr ora

  When RMAN duplicate is executed, the following error is reported and then interrupted:   Dbgsql: Target> begin: fhdbi: = dbms_rcvcat.getdbid; end; Dbgsql: sqlcode = 6550 Dbgsql: B: fhdbi = 32767 RMAN-00571: =========================================

    A set of DG built by a friend has been tossing for a long time and has always reported the following error: ORA-12514: TNS: Listener does not currentlyknow of Service requested in connect Descriptor Ping [arc2]: Heartbeat failed to connect