Oracle

(1) In ORACLE:Insert into product(ID, names, price, code)Select 100, 'A', from dualUnionSelect 101, 'B', from dual;It is best to use an insert statement here. Otherwise, the efficiency is not high. Multiple select statements are used.   (2) In

SQL Server can use the top N method, which is used in OracleRownum, but if onlyRownum randomly retrieves data. If you want to obtain the first few data entries in a certain order You can write as follows:Select * from (Select column from table

The instr syntax is as follows:Instr (string1, string2 [, start_position [, nth_appearance]) Function Description:This function returns the position of string2 in string1. Start_positionThe parameter indicates the number of characters starting

Reproduced original address: http://blog.csdn.net/zftang/article/details/6586996We all know that a trigger does not require commit and cannot be written to it. The trigger and the DML that triggers it are the same transaction.DML is submitted, and

Next to the previous log: ubuntu10.10 installing the Oracle client   When I first installed sap, sapsr3 or sys failed to connect to the service. Sapsr3 indicates that the select any dictionary permission is missing, and SYS prompts that the user

First, use the expdp tool to create a backup script: Backup. Sh       # Hs_aws_db PRD backup # By xulong #2010-09-25 export oracle_sid = hsoa export oracle_unqname = hsoa export oracle_base = /home/Oracle export oracle_owner = OA

The company needs a collaborative system. To ensure stability, the system runs in Linux, and the database uses oracle. The overall installation is relatively simple. Here we record the installation process and the details to be noted.   1. When

After the local Oracle connection is created, it is the GBK character set by default. If the connection server is not the same GBK character set, Chinese garbled characters may occur, in this case, we need to modify the local character set to match

When installing the database instance, the system will select the country character set: Country: database character set. If the character sets of the two Oracle servers are different, it will be very troublesome during data migration. View the

1. Simple Explanation of primary key and rowidPrimary Key: The primary key is unique and not empty. It is used to identify a unique record.Rowid: the actual physical address of the Data. You do not have to create a rowid yourself. You do not have

1. Run the lsnrctl status Command to view the instance status. HS-PRD: oraprd 17> LSNRCTL status LSNRCTL for IBM/aix risc system/6000: Version 10.2.0.2.0-production on 04-ja04:37:52 2012 Copyright (c) 1991,200 5, Oracle. All rights

# Login # login development machine # login SSH oa@192.168.1.9 # Database Export export nls_lang = american_america.zhs16gbk export F1 = 'date + % Y % m % d % H % M '. DMP expdp/'sys/pwd @ orcl as sysdba/'directory = data_pump_dir dumpfile = $

Recently, due to business needs, I want to pass. net direct connection to the SAP background database, we use Oracle, and we have never touched on Oracle connections before, especially because SAP's Basis Implementation documentation is incomplete,

// Aggregate FunctionMax, Min, AVG, Count, Sum Select count (*) from Dept;Select count (deptno) from Dept; // User, decode, nvlSelect User from dual;Select sum (decode (A1, 'abc',), sum (decode (A1, 'bca',) from AA;Select A1, nvl (A2, 'null') from

-- Create Test Data Create Table A (ID number ); Create Table B (ID number ); Insert into a values (1 ); Insert into a values (2 ); Insert into a values (3 ); Insert into B values (1 ); Insert into B values (2 ); Insert into B values (4 );

Create a user's standard syntax (Oracle9i) Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--> Create user identified {By password | externally | globally as 'external _ name '} [{Default

To enable external processes to access the Oracle database, you must configure the Oracle network server environment.Listener. ora/sqlnet. ora and tnsnames. ora are all three files.Tnsnames. ora: defines one or more network services. net service

Oracle data type conversion Oracle data type conversion includes explicit data type conversion and implicit data type conversion. In general, implicit data type conversion is available, but we recommend that you convert the display data type to

A manager from IBM came to the company a few days ago. He wanted us to use the DB2 database and talked to us about the relationship between SAP and Oracle. Many years ago, SAP and Oracle were very good partners. One was the ERP leader and the other

No1: select an optimizer. NO2: Shared SQLTo avoid repeated parsing of the same SQL statement, Oracle stores the SQL statement in memory after the first parsing. the memory in the shared buffer pool of the SGA (system global area) can be shared by