Oracle

Basic PL/SQL settings 1. How to export table creation statements in batches? Select [Tools]-> [Export User Objects...] from the menu, and select the table to be exported in the window that appears. The SQL script exported in this way does not

Oracle-DBLINK Analysis of ORACLE build DB-LINK Test Conditions www.2cto.com two servers remote: IP: 192.168.0.18, SID: usertest, Username: usertest, password: 123456 local: IP: 192.168.8.90, SID: wjn, username: userwjn, password: mosquito0 parameter

Precautions for oracle full offline backup: Full offline backup, also known as cold backup. The existence of cold backup is to protect the site, so that we can start from scratch when recovery fails.We know that the data file is the disk space

Oracle user creation and permission operations (oracle study Note 1) 1. create userSQL> create user arthur identified by m123 (m123 is a password and must start with a letter) normal users do not have the permission to use create user. Users can be

Oracle (1) authentication mechanism and three authentication mechanisms for User Creation and database modification: operating system verification Password File verification database verification note: sys users only need OS verification and

How to calculate the optimal undo_retention and the initial experience of undo_retention In the undo series is simply defined as the minimum retention time of the most data. In AUM mode, the undo_retention parameter is used for the time when undo

An in-depth exploration of the oracle rollback mechanism the undo mechanism is a clever feature of oracle and one of the difficulties in learning oracle. Next we will learn more about it internally. Session 1: scott user, initiates a transaction

In Linux, completely delete oracle step 1. Disable the oracle server and background process 2. Stop the oracle listener 3. Delete All subdirectories and files in the $ ORACLE_HOME directory (note: there will be an alarm when Deleting Users and user

When oracle Objects migrate IMP data in tablespaces, the imported and exported tablespaces are different and the imported data is in the system tablespace. Therefore, the tablespace needs to be moved to the user tablespace. The specific process is

The oracle Database Log File version is inconsistent. When the test database is started in the morning, the following problems are found: the database version is 11.2.0.3SQL> startupORACLE instance started. total System Global Area 1653518336

The impact of the value specified by autoextend on next on the performance of the tablespace corresponding to the file. Creating a tablespace is a data file that can be set to automatic expansion and how much capacity can be expanded each time, if

Install oralce 11g full version in centos linuxSystem Environment: CentOS 5.5 64bit Software Version: linux. x64_11gR2_database_1of2 is good. Now you can install: 1. hardware requirement: memory: grep-I memtotal/proc/meminfo officially requires at

In practice, the best practice of oracle password operations is that oracle password operations are implemented through profile, while resources are controlled by resource consumption groups. profile is actually a limitation. Use profile to control

Environment: Oracle 11g R2 + SQLPlus problem: Oracle cannot log on with the scott user, prompting that the lock has been applied. Solution: Open SQL Plus ------------> run the following command [SQL] conn system/manager; alter user scott account

The SQL statement for the first n records of each group after grouping in oracle: rownumber () over () row_number () OVER (PARTITION BY COL1 ORDER BY COL2) indicates grouping BY COL1, sort by COL2 in the group, and the value calculated by this

How to sort null values in the date Field Type in oracle Database Java codeIn the oracle database, if a field type in the table is date and the field type has null values and needs to be sorted, the solution for www.2cto.com is to use the nvl

In Oracle Database, the storage of null values mainly verifies the storage of null values of the number and varchar2 data types. First, we will introduce the structure of row piece, A rowpiece (not including cluster table and chain row) includes row

How to completely kill locks and release resources Oracle Database Administrators often encounter the following problem: a process in the "killed" status has been locked for a long time and will not be released. The usual practice is to restart the

ORACLE table connection   1. What is table join?Table join refers to the association between tables in an SQL statement to retrieve relevant data from one or more tables. Ii. What table connections are used by the ORACLE optimizer?1. NESTED LOOP

View the oracle Execution Plan (command implementation). See the following small exercises to show you how to use oracle commands to view the execution plan. www.2cto.com 1. SQL statement to view the law enforcement plan: SQL code explain plan for