Oracle

Here are some examples to understand Oracle's knowledge pointsUser Login (skip user name and password login):Sqlplus/nologConnect/as SYSDBAA. User1. Create a user (example)Create user Olay identified by 123;2. Delete the user (along with the objects

Today, after the virtual machine installed the Oracle database restart system to enter the database and found the following error:The reasons for ORA-01034 and ORA-27101 are manifold: Oracle's current service is unavailable, andshared memory realm

1. Sybase and Oracle Comparison http://blog.itpub.net/14067/viewspace-1030014/Oracle employs a multi-threaded, multi-process architectureSybase uses a single-process multi-thread architectureBoth Oracle and Sybase use multiple threads.The multi-clue

Create or Replace function isexist (data in datatypes) --datatypes is the type of the data in the tablereturn numberIsV_flag number (2);V_data [datatypes]; --Types of data in tablesBeginSelect data into V_data from table_name where ...;If v_data

Core tips:function is used to return specific data. When executing, we need to find the return value of a variable receiving function; The syntax is as follows: Create or Replace function function_name (argu1 [Mode1] datatype1, argu2 [Mode2]

Oracle Database Features: High security, rich data typesOracle is a database product developed by Oracle Corporation of the United States----------------------------------------------------------------------Oracle version:OracleOracle8i--------------

(1) The Code of the Lock table query has the following form:Select COUNT (*) from V$locked_object;SELECT * from V$locked_object;(2) See which table is lockedSelect B.owner,b.object_name,a.session_id,a.locked_mode from V$locked_object a,dba_objects b

Oracle Initial PasswordDefault User name and password[Oracle Initial Password]:Internal/oracleSys/change_on_installSystem/managerScott/tigerChange PasswordDosSqlplus/nologConn/as SYSDBAAlter user user identified by passwordHow Oracle can see which

It's done 2 o'clock in the morning every day.Dbms_job.submit (V_job, ' lv; ', TRUNC (sysdate+1) +2/24, ' TRUNC (sysdate+1) +2/24 ');And the definition job, it's best to define it.Declare job1 number;begindbms_job.submit (job1, ' lv; '), TRUNC

2015-11-20RMAN>Sql'ALTER DATABASE open Resetlogs'; SQL statement:Alter Database OpenResetlogsrman-00571:===========================================================RMAN-00569:===============ERROR MESSAGE STACK follows===============RMAN-00571:========

ObjectiveWe know that the various name types in Oracle often appear in our individual profiles, roughly the following:There are db_name,instance_name,service_name in Init.ora.When configuring the DG, use Db_unique_name to differentiate the master

/*in the actual use of SQL work will always encounter the value of a column to be displayed in the title. Is the total said the ranks of the conversion or interchange. For example, there is the following data: ID NAME kecheng Chengji-----------------

Introduction to paging query of mainstream databases and paging of mainstream Databases1. Background Because a project needs to display a large amount of data on the page, all data is first queried during database query and then displayed, at this

Introduction to Oracle system processes and main functionsIntroduction to major Oracle Processes Data Writing Process (dbwr): responsible for writing changed data from the database buffer cache to the data fileLog write process (lgwr): writes

Summary of oracle flash back technology: Flash back query (DML)We need to display the time in set time on; to display the time. Delete the table first, and insert several rows of data. SQL> set time on; SQL> create table emp1 as select * from scott.

NVARCHAR2 Character Set mismatch in Oracle, oraclenvarchar2 An error is returned when NVARCHAR2 type is encountered during character matching in Oracle, prompting that the character set does not match. To use NVARCHAR2, You need to convert the

NVARCHAR2 Character Set mismatch in OracleAn error is returned when NVARCHAR2 type is encountered during character matching in Oracle, prompting that the character set does not match. To use NVARCHAR2, You need to convert the fields and add to_char (

Optimize distinct and oracledistinct using group by in oracle Today, mentor provides an SQL statement optimization task. (The environment is SQL developer) there is a statement that runs very slowly, and the query results have 17544 records, but it

A simple method to update two tables at the same time in the Oracle database. Previously, I only wrote some simple updaet statements, such as updae table set c1 = 'xxx '. Today, I encountered A data correction problem. The project background is as

Automatic installation and configuration of oracle 11gPreparations before Database Installation [Root @ localhost ~] # Vim/etc/sysconfig/network-scripts/ifcfg-eth0 # configure the IP address DEVICE = eth0HWADDR = 00: 0C: 29: 59: 6E: BFTYPE =