Oracle

Recently there was a problem when I installed Oracle,Oracle 11g Ora-12514:tns: The listener does not currently recognize the requested service in the connection descriptorPreviously installed Oracle many times Online search a lot of methods or can

ConceptWhat is an Oracle database?Basically, there are two main components of the Oracle database-the instance and the database itself. The instance includes some memory structures and background processes, while the database refers to disk

CREATE OR REPLACE FUNCTION chi2num (chivalue in VARCHAR2) RETURN number isTYPE MAP is TABLE of Binary_integer INDEX by VARCHAR2 (10);Ling_jiu_map map;Shibaiqian_map map;Wanyizhao_map map;--Temporary variablesI INT: = 0; --' Temporary variableK INT: =

1. Enter the menu file-reverse engineer-database ...2. Open the window, select the database version, click "OK"3. Open the window and select Usering a data source:4. If there is already a DCP file, click OK directly, if not, select the Select File

One, the basic type of sub -Query multiple rows subquery(1) Use the in operator for multi-line subqueries. (Summary: Multiple rows of subqueries available after the in operator)For example: Query the highest-paid employee information for each

Preparation: Download the virtual machine Oracle VIRTUALBOX,CENTOS-6.5-X86_64-BIN-DVD1 First1: Installation Virtual Machine Oracle VirtualBox, relatively simple, all the way next can, needless to say, not the ferry2: After installing the virtual

Navicat for Oracle is a client tool for Oracle databases. With this client, we can manipulate the Oracle database in a graphical manner.The Oracle database version that explains our trial is Oracle 10G Express Edition, which is what we call Oracle

650) this.width=650; "id=" aimg_rao1z "class=" Zoom "width=" "src=" https://img.alicdn.com/imgextra/i2/332189337/ Tb2tll.bxxxxxblxxxxxxxxxxxx-332189337.png "border=" 0 "/>650) this.width=650; "id=" Aimg_ixnfi "class=" Zoom "width=" "src="

1. The limit usage of MySQLWhen we use query statements, we often have to return the first few or the middle of a few rows of data, this time what to do? Don't worry,MySQL has provided us with such a feature.SQL code SELECT * from table

Oracle SQL Developer is a very powerful open source SQL development tool, but recently I began to study it, just installed Oracle SQL Developer is not supported to connect MySQL, need to download the JDBC driver formysql from the MySQL official

In Oracle database systems, the parameters that play the role of tuning are called initialization parameters, which are recorded in the Initsid.ora file in Oracle 8i and previous versions, while Oracle 9i/10g/ These parameters are recorded in the

The Oracle database backup feature, which was implemented very early today, was written at the university stage design time:Import java.io.file;import java.io.ioexception;/** * Oracle Database Backup * * @author Gaohuanjie */public class

One. Inquiry article1. Querying the usage of Oracle TablespaceSelect b.file_id file ID,B.tablespace_name table Space,B.file_name Physical file name,Total number of bytes b.bytes,(B.bytes-sum (NVL (a.bytes,0))) has been used,Sum (NVL (a.bytes,0))

Instance 1--IF statement/* Web Oracle Database development must be pl/sql_2-3Determine the number the user has entered from the keyboard1. How to use the IF statement2. Receive input from a keyboard (string) */Set serveroutput on;--Receive a

1 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here

DML (Data Manipulation language):Data Manipulation Language , the language that operates on data in the database, including command Select, UPDATE, INSERT, DELETE, call, EXPLAIN PLAN, LOCK TABLE. Details are as follows:1) Select-retrieve data from

Summary of advantages and disadvantages of ORACLE five tables:1. Normal table (heap table): Suitable for most design scenarios, with advantages and disadvantages.Strengths:A, the syntax is simple and convenientb, suitable for most

Virtual machine environment, OEL7.2, ORACLE 12.1. After restarting the host, it appears that the listener started for almost 1 minutes.Here is the analysis process:Perform a listening start operation, hang up for a while, and finally listen to start

SAP R3 Oracle 9i Client InstallationThe client system is R2 64-bit for Windows Server.Oracle database services are configured in two ways: 1. Configuration during installation, 2. Configuration via NET Configuration Assistant, Oracle database

Maven is a project management and building automation tool. But for our programmers, our greatest concern is its project-building capabilities. So here's how we're going to use Maven to meet the daily needs of our project.The Maven usage convention