Oracle

first, create a table space1. Set the instance nameEcho $ORACLE _sidExport Oracle_sid=mvbpbang2, sqlplus login/sqlplus Command LoginWhen you install Oracle, you need to remember the set global database name (default = ORCL) and password when you log

I. Overview　　Main content:　　Second, sub-query introduction　　1. Simple subquery (where subquery)SELECT last_name from Employees WHERE > (SELECT salary from employees WHERE =149);　　2.

SQL execution efficiency has a significant impact on system usage, and this article summarizes some of the solutions to Oracle optimization problems that are encountered in troubleshooting problems, or the daily learning gains. 1.Oracle SQL

View database status (normal user login to ensure the database is open state)Sql> select status from V$instance;Create User ( new user needs to grant connection permissions to connect to database )Sql> create user User1 identified by

Expression: NVL (filed, replace)The function of the NVL function is that the value of the field that is encountered in the query is NULL, replace NULL with replace, and change its null query value.NVL can convert any data type, but only if the type

I. Overview　　Categories of permissions:　　　System permissions: Permissions for the databaseObject permissions: Permissions to manipulate database objectsBasically, the control of permissions is interlinked with the management console described

1. Querying duplicate dataSELECT * from table name where repeating field (general primary key) in (Select repeating field from table name group by repeating field having count (wf_oid) >1)Select repeating field, COUNT (*) from table name Group by

Oracle Lock table is relatively simple, the session of the query lock table can be killed.1, the following are related to the tableSELECT * fromV$lock;SELECT * fromV$sqlarea;SELECT * fromv$session;SELECT * fromv$process;SELECT *

Navicat cracked version download (after installation, click to execute the last cracked file can be)Link: Https://pan.baidu.com/s/1pMpVwfT Password: vrt6Connect Oracle also need to download the following files, Oracle official website need to

How to export and import scripts in oracleExport Export all tables under a specified user # Environment variable setting export ORACLE_SID = bdyzexport ORACLE_BASE =/u01/oracle11g_R2export ORACLE_HOME = $ ORACLE_BASE/11 gexport LD_LIBRARY_PATH = $

Oracle filters repeated records of a field and obtains only one record. The oracle Field I. First thought: 1. Keyword distinct 2, group A function such as 3, MAX, and MIN is called a clustering function, which is used together with a GROUP. But none

Steps for installing oracle 11g image in win7, win711g 1. First, prepare the Installation File oracle11. 2. Find setup.exe in the oracle11folder and double-click it to run 3. In configuration security updates, enter frequently-used emails (optional)

How can I check whether the oracle database is started in archive mode ?, Oracle Archiving [1] 1. select name, log_mode from v $ database; NAME LOG_MODE ------------------------------------------ QUERY NOARCHIVELOG 2. Use the archive log list

Six TNS in Oracle Database: solution to protocol adapter errors, oracletns No one would deny that ORACLE is one of the most influential database products in the world; but good things do not seem to be so useful (it seems at first ), even a bit

Step for installing oracle11g in tar mode, taroracle11g Install oracle11g using tar In the dual-host database cluster built by veritas, the configuration and installed software and hardware environments of the two servers are the same. After an

Step-by-Step tutorial on deploying an Oracle database with tar: deploy an oracle database with tar There is a project on hand that may require downtime and maintenance, and it is likely that the host fails to be started. In case of a temporary

The problem of flute product in SQL and multi-table join operations, SQL flute (Scott account)   SELECT * FROM scott. dept; -- 4SELECT * FROM scott. emp; -- 14 /**Cartesian ProductInternal Connection (equivalent connection)External Connection

The usage of start with in oracle Database, oraclestart Oracle provides the start with connect by syntax structure to implement recursive queries. 1. A simple example: SQL> select * from test; BILL_MONTH DAY_NUMBER MSISDN ---------------------------

How to use oracle sqluldr2, oraclesqluldr2 Introduction: The oracle data export tool sqluldr2 can export data in csv, txt, and other formats. It is suitable for exporting large volumes of data and is very fast. After export, you can use oracle

Detailed description of oracle table preparation, index testing, SQL query execution times, And tablespace creation methods. oraclesql Put a system diagram first, Table preparation Create table t as select * from all_objects;Index test Create