Oracle

Implementing select Top N in Oracle:Because Oracle does not support the SELECT top statement, it is often used in Oracle with order by and RowNumTo implement the query for select top N.To put it simply, the implementation method is as follows:Select

Completely remove the original Oracle in Windows and then reinstall the Oracle database. The steps are as follows:1. Start-> Setup-> Control Panel-> Management Tool-> Service to stop all Oracle services.2. Start-> Program->oracle-orahome81->oracle

There are several views related to object permissions, tab represents table permissions, and col represents column

If you have the following table structure AAAA, use a field prev_id to indicate the order of the records, to sort them, need to use the recursive function Id prev_id CONT 99 A

oracle11g changing the character set Al32utf8 to ZHS16GBKWhen the original installation of Oracle selected by default installation, the result character set is not used in the 16GBK, to change the character set, from the Internet to find a method

Oracle Case When usage introduction1. Case-When expressions have two forms--Simple Case function Case Sex When ' 1 ' Then ' men ' When ' 2 ' then ' women ' Else ' other ' END --case search function CaseWhen sex = ' 1 ' Then ' man ' When sex =

Oracle Performance AnalysisSoftware Environment: Oracle 11g, dual-machine RAC.Problem:Large table (Tens) query, slow operation, often timeout terminal (ORA-01013: User request to cancel the current operation)Analysis:1) partition Table2) Historical

Oracle tells Google that it lostBoxi2016-05-27 ? Big company Google says the jury's recognition represents the triumph of the Android ecosystem, the Java Development Community, and software developers who are relying on open, free programming

Permissions:Create sessionCREATE tableUnlimited tablespaceConnectResourceDbaCases:#sqlplus/nologSql> Conn/as sysdba;Sql>create user username identified by passwordSql> Grant DBA to username;Sql> Conn Username/passwordSql> select * from

We know that the Oarcle database really holds the data file (data files), the oarcle tablespace (tablespaces) is actually a logical concept, and he does not physically exist, so a set of data files will be a table space to twist together.Table Space

This article transferred from: http://blog.csdn.net/ludongshun2016/article/details/71453125The fields in the database are number types, and the corresponding integers and bigdecimal in the Java type will appear;The test found that when the database

Case: Open card information in the bank Field Field type Id Number Name VARCHAR2 (64) Sex CHAR2 () Birth Date Money Number (10,2)

1. After extracting the Oracle compressed files, open the directory and double click "Setup.exe" to start the installation.2. "Oracle Universal Installer" window pops up3, e-mail prompts, follow the default next action4, the second step directly

First, the introduction of Sql_trace--Open trace file settings and set SQL Trace to True to add a TRC file to the Udump directory.Alter session set Sql_trace=true;Show parameter Sql_trace; (SELECT * from V$parameter where name= ' sql_trace ';)Does

To see if the XXX table space is auto-extended:Select file_name,autoextensible,increment_by from Dba_data_files;Select file_id,file_name,tablespace_name,autoextensible,increment_by from Dba_data_files order by file_id Desc;To open the table space

Oracle creates a normal user and gives permissions1) using SYS or system/manager as SYSDBA; Connect to the database.2) Create peng:create user Peng identified by pwd_oracle;Delete users, drop user peng;3) grant the user permission to log on to the

Defined:A tablespace is a logical concept in which all data and structure information is stored in one or more data files, and the tablespace is part of the database. The database comes with several table spaces, such as system,temp. The general

Recently, because the table space of the customer data in the business is occupied too large, and want to reduce the size of the tablespace file by deleting some data, it is possible to use partition table to implementPartitioned tables are divided

1, open the terminal, enter the following command;[Email protected] ~]# export display=localhost:1[Email protected] ~]# Xhost +2. Switch to Oracle user and use the following command:[Email protected] ~]# su-oracle3. Specify the variables and values

Delete statementBasic syntax:Delete from table name where conditionPrecautions:1, if you do not use the WHERE clause, all data in the table is deletedDelete from test;2, if you want to delete the value of a column, delete is not possible3, delete