what is table index

What is Hashtable? Hashtable is a synchronous implementation of map interface based on hash table The key of the element in the Hashtable is unique, and the value can be repeated The key and value of the elements in the Hashtable

Recently busy, want to study with you and discuss some of the Java source code and its implementation of the data structure, Not a high-level thing, an interested casual look 1. Why map, take HashMap as an example Many times we have this requirement,

Inaccurate analysis and avoidance methods 1 Case visits Hardware environment: IBM xseries 3650 Operating system: WINDOWS2003 Standard Version +SP02 Database version: Oracle9.2.0.1 Pl/sql Developer Version: 7.0.2.1076 As a result of business

Package COM.HEPHEC;Import Java.util.Arrays;Public class sequencelist{Creates a sequential linear table with an array of specified lengths//@paramElement Specifies the first element in a sequential linear table//@paramInitsize the length of the

The basic content of the index is described in the previous article, and we continue to introduce the index optimization combat. Before introducing the index optimization practice, first introduce the two important concepts related to indexes, which

After PAE is turned on, the structure of the 32-bit linear address has changed, with the following structure30-31-bit: Page directory pointer table index21-29-bit: Page Catalog index12-20-bit: Page table index0-11-bit: in-page offsetAfter PAE is

I. SummaryIn the normal storage and database migration, when encountering a large database when using exp often takes a few hours, time consuming. oracle10g later can use EXPDP to export the database to spend much less time than Exp spent, and the

DB2 9's adaptive utility throttling system enables maintenance during busy hours. If you want to keep your car in good state, you must perform regular maintenance, such as oil change and spark plugs. This is also true for databases. if you want to

Oracle (2) DDL statement create, alert, drop, truncate II. data Definition (DDL) Section www.2cto.com 1. CREATE (create table, index, view, synonym, process, function, database link, etc.) Common ORACLE field types include CHAR fixed length string

We all know the actual application optimizer for PL/SQL statement execution in Oracle databases, which has cost-based related optimizer CBO) and regular-based optimizer RBO ). The actual Optimization Method of RBO depends on a set of strict syntax

Dba_indexes and dba_ind_columns are required to view table index information, including the script WITHnonformatAS (S Dba_indexes and dba_ind_columns are required to view table index information, including the composite index Script: WITH nonformat

The following articles mainly describe the Distributed Management of DB2 9. In this column, we will explain the actual operation steps for performing automatic maintenance, it also describes how to use the utility to throttle if maintenance

Optimizer for PL/SQL statement execution in Oracle databases, including cost-based optimizer (CBO) and rule-based optimizer (RBO ). The RBO optimization method depends on a set of strict syntax rules, as long as the statements written according to

Optimizer for PL/SQL statement execution in Oracle databases, including cost-based optimizer (CBO) and rule-based optimizer (RBO ). The RBO optimization method depends on a set of strict syntax rules, as long as the statements written according to

Copyright statement: Reprinted with a hyperlinkArticleSource and author information and this statementHttp://cjbskysea.blogbus.com/logs/48140313.html The basic function library is the built-in function library of Lua and does not require

Collect statistics from ORACLE Link: http://blog.itpub.net/2317695/viewspace-1226138/Today, I saw an article on Statistics Collection on the Internet, which is not bad. 1. Understand what is statistical information Optimizer statistics are a set of

The basic function library is the built-in function library of Lua and does not require additional loading. Assert (V [, message])Function: equivalent to the assertion of C,Parameters:V: When expression V is nil or false, an error is

1.1.1 Summary If we want to optimize the database, we can optimize the database system using the following five methods. 1. Computer hardware optimization2. Application Optimization3. Database INDEX OPTIMIZATION4. SQL statement Optimization5.

The ORACLE tutorial is: several methods to optimize the design of Oracle database tables. Preface Most Oracle Database performance problems are caused by unreasonable Database design. Only a small number of problems are rooted in the unreasonable

Reference: linuxfun. me? For those who have used MySQL in p1263, The MyISAM Table engine is the most frequently used at the beginning. The database of this engine creates three files: Table Structure, table index, and table data space. You can