Oracle

An Oracle cursor is divided into a display cursor and an implicit cursor. Display cursor (Explicit Cursor): A cursor defined in a PL/SQL program, used for querying, is called a display cursor.Implicit cursors (implicit Cursor): A cursor that is

Discover Navicat as a database-connected tool that really works well, the visual interface looks a lot more comfortable, here are some of the issues I have today when connecting to the Oracle database:1, after the installation of Oracle directly

1. Database availability, DBA says "not counted"-materialized view, faster query speedAt some point, the availability of the database is not set by the DBA. Because even if the DBA has absolute control over the database, users may feel differently

There are two kinds of functions in this function:the first, that is, everyone is more familiar with the removal of space. Example:--trim to remove spaces before and after a specified charactersql> SELECT TRIM (' DD DF ') from dual;TRIM (' Dddf ')---

Using shell scripts to monitor and manage Oracle databases will greatly simplify the workload of DBAs, such as common monitoring of instances, monitoring of monitors, monitoring of alarm logs, backup of databases, automatic mailing of AWR report,

SQLLDR ToolsThe Sql*loader client tool is Sqlldr, enter SQLLDR under the command line of the operating system, and then do not take any parameters, and the Help information shown below (a simple description of all command-line arguments and their

RBO and the basic concept of the CBOThe optimizer in the Oracle database is also called the query Optimizer. It is an optimization tool for SQL analysis and execution, and it is responsible for generating and developing SQL execution plans. Oracle's

Extract the contents of the tables and LOB fields in the database files in the damaged disk by using the Oracle Dul toolIn a 8i library recovery, as hard disk damage caused a number of tables to have a lot of paradoxical bad blocks, trying to use

Case one: Login with SqlplusNormal input username password, will be error, because SYS is a super administrator outside the database, so when we log inTo enter a password: password +as sysdba (for example: 123456 as SYSDBA)Scenario two: Log on with

SQL Optimization Tips (1):Connection order in the WHERE clause: Oracle parses the WHERE clause in a bottom-up order, and according to this principle, the connections between tables must be written before other where conditions, those that can filter

650) this.width=650; "Src=" Http://s4.51cto.com/wyfs02/M02/8C/13/wKioL1hhJnvjwkHvAABh8bZO-Vc778.png-wh_500x0-wm_3 -wmp_4-s_2715184897.png "title=" 1.png "alt=" Wkiol1hhjnvjwkhvaabh8bzo-vc778.png-wh_50 "/>Classification of functionsSingle-line

Sharing a form to generate Excel file for SQL query in Oracle Forms.   This form can is used in Oracle Forms 6i and 10g/11g. Below is the shot of this form and could was download from the following LINK:EXCEL_REP.FMB A procedure Create_ Excel_file

What is checkpoint?Checkpoint in an Oracle database is the event that forces the dirty data in memory to be written to disk, which is to keep the data in memory consistent with the data on the disk. The SCN is used to describe the exact point in

First, the preparation of the main library side1. View the database directory structure in the main libraryTo view the database file pathSelect T1.name,t2.name from V$tablespace t1,v$datafile T2 where t1.ts#=t2.ts#;View Log file pathSELECT * from

Download the 3 required packages (in order to connect the 11g database)1:oracle Client (Oracle clients)Http://www.oracle.com/technetwork/cn/database/enterprise-edition/downloads/112010-win64soft-086667-zhs.htmlDownload Win64_11gr2_client.zip

Count Detailed:   COUNT (*) returns the total number of rows that exist in the table, including rows with a value of null, whereas count (column name) returns the total number of all rows except null in the table (columns with default values will

When using PL/SQL, the first time you open the table, you will be prompted to "dynamic execution table is inaccessible, automatic statistics of this session is forbidden" error, a message is as follows: V$session,v$sesstat,v$statname is not

OS:Oracle Linux Server Release 5.7Db:Oracle Database 11g Enterprise Edition Release 11.2.0.3.0-64bit Production1. Check the Listening status:sql>!lsnrctl StatusLsnrctl for linux:version 11.2.0.3.0-production on 12-nov-2013 01:36:29Copyright (c) 1991,

1, block, the concept of bufferThe concept of section block and the concept of the block are introduced.The concept of buffer2. The meaning of buffer cacheReduce IOPhysical IO: Disk readLogic IO: Memory readConstruction of CR blocks: later

Oracle learning notes 4 SQL commands (2): SQL operation language category, oracle learning notes SQL is classified into the following language categories1. Data Definition Language (DDL)Create, Alter, Drop 2. Data manipulation language (DML)Insert,