Oracle

A B-Tree index has only one root node, which is actually the topmost branch node in the tree. You can use the following figure to describe the structure of the B-tree index. where b represents the branch node, and L represents the leaf node. For a

Environment: Oracle 11g R2 + sqlplus Issue: Create user, create table with ORA-01950 error on tablespace ' system ' without permissions Resolution: This problem, obviously, is the issue of permissions. After the user is created, the permissions

1 Status Query launch status SQL Statement /p> results Nomount Select Statu s from V$instance; started select Open_mode from v$database; ERROR at line 1:

First, use the Decode function for row-column:First of all, let's look at the most typical requirements: Student transcript report making "1" Table structure definition: CREATE TABLE SCORE ( ID Number (2), Student_name VARCHAR2 (10), SUBJECT

To modify the number of Oracle connectionsProblem Description: Client Connection Database error Resolution process: 1. View the current number of sessions, processes, and sessions values, and found that the values of the session

Author: eygle | Chinese Version "When reproduced, please indicate the source of the article and the author's information and this statement in the form of a hyperlink"Links: http://www.eygle.com/archives/2009/02/oracle_exp_00003.html site Related

Instructions for use:1, Long data type is stored in variable-length strings, the maximum length limit is 2GB. 2, for more than a certain length of text, the basic only long type to store, the data dictionary many objects are defined in a long to

Sequence in Oracle is the serial number, which automatically increases each time it is fetched. Sequence is not related to the table. 1, create Sequence first to have create Sequence or create any Sequence permissions. The statement is created as

Xml GetCity com.yyb.servlet.getcity getcity /getCity index.jsp regions=pdao.findallprovince (); Request.setattribute ("Regions", regions); %> Provincial and County three-level linkage Please

the SQL for creating tables and preparing table data is as follows: CREATE TABLE aaa ( Age number,--agesName1 VARCHAR2 (20)--Name)INSERT into AAA VALUES (23, ' John ');INSERT into AAA VALUES (24, ' Dick ');INSERT into AAA VALUES (23, ' American

Oracle's indexes can be grouped into 5 categories, including unique indexes, combined indexes, reverse key indexes, bitmap indexes, and function based indexes. 1. Standard syntax for creating indexes The following refers to the content: CREATE index

Introduction to Oracle Partitioning table technology Oracle provides partitioning technology to support VLDB (Very Large DataBase). The partitioned table puts different records of the partition columns into different partitions by judging the

--oracle How to bulk export the database table structure (build table statement)--1. Use the System user creation path Utl_dir to hold the file-D:\HSX\DBA must be a pre-existing directory create or replace directory Utl_dir as ' D:/HSX/DBA '; --Log

Oracle partitioned tables into different table spaces Reference: http://hougbin.iteye.com/blog/1470505 Blog Categories:Database query partition: Select *from user_extents WHERE partition_name= ' partition name '; 1 Create a table space Create

In the background of a news web site monitoring process, often the database began to use the swap partition, and in turn, the entire application system response is very slow, can not provide services. The server's memory is set to 4G,PGA set to 1G

Oracle does not distinguish between tables or indexes in the table space, all the tables and indexes can be placed in the same table space when the amount of data is more than an hour, but as the volume of data increases, it is best to store the

Select sequence name. Currval from dual; Gets the current value of the sequence, which is variable. It is to be noted that: After a successful database connection, the first execution of this sentence, will report an exception, can not be used.

In ORACLE database, you need to SQLStatement to optimize the words need to know its implementation plan, and accordingly to adjust. There are several ways to get Oracle's execution plan, and here's a summary1, the use of explain     Oracle RDBMS

Page-Search column ambiguously defined columns not explicitly defined SELECT *From (select Abc.*, RowNum mFrom (select T.oid,T.clues_code,T.clues_name,T.customer_name,(Select A.fullnameFrom Ecc_prm_areainfo Awhere A.ennable_flag = ' T 'and a.oid = T.

Oracle database Installation diagram and graphics operation stepsFirst, Oracle downloadNote that Oracle is divided into two files, and after downloading, two files are extracted to the same directory. In the path name, it is best not to appear in