Database Administrator

1. To establish a Database connection, you must have the PCREATE Database link system permission. to connect to a remote account, you must also have the CREATE session common permission;2. Ensure that connected users have the permission to access

Environment: DB: 11.2.0.2 rac OS: RHEL 5.6 The following problems are encountered when upgrading a single machine to RAC under Oracle 11gR2 today. [Oracle @ 11rac5 ~] $ Sqlplus/as sysdba   SQL * Plus: Release 11.2.0.2.0 Production on Tue Oct 9 19

The Value Type of the hiredate column in the emp table updated today is date. Use the first statement update myemp set hiredate = '2017-03-06 'where ename = 'liutao '; Unsuccessful If this is not the case, use update myemp set hiredate = '03-06-85

I. Common connection query methods in Oracle (exercises with built-in oracle tables) 1. left outer join (left outer join/left join) Left join is based on records in the left table. All records in the left table are displayed. Only records meeting

Under multiple instances: You can bind a cpu to prevent mutual interference between multiple instances. Mongodb memory can also be restricted to the master to prevent all memory occupied by one instance. Ulimit-s 4096 & ulimit-m 31457280 & sudo-u

Installation version: mysql-5.5.27.tar.gz 1. Install the cmake compiler. 1) download cmake # Cd/usr/local/src # Wget http://www.cmake.org/files/v2.8/cmake-2.8.3.tar.gz 2) decompress cmake # Tar-zvxf cmake-2.8.3.tar.gz 3) Configure Compilation # Cd

Mysql replication is completed asynchronously by default. The semi-Sync Mode is a patch developed by google for mysql. This function has been integrated in Mysql 5.5 or later versions. Semi-sync means that the MASTER only needs to receive the

From the following experiment, we can see that the full table scan is performed to retrieve data according to the extent/block sequence. The first experiment had a 'db file scattered read' wait event, and the second experiment had loaded the data

Environment: CentOS 5.5 32-bit Oracle 10g Preparations before installation: Download epel Source Http://dl.Fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm [Root @ localhost ~] # Rpm-ivh epel-release-5-4.noarch.rpm [Root @ localhost ~] #

Master database:-- Check whether archiving is enabled for the master databaseArchive log list; -- If archive is not enabled for the master database, archive is enabled.-- Set the archive pathAlter system set log_archive_dest_1 = 'location

Cause: because a data file in the Oracle database is accidentally deleted, the Oracle-related services on the control panel are started, but SQL * Plus cannot be connected. Solution: You can open the database by taking the data file offline

I. Mysql Binlog format Introduction Mysql binlog has three formats: Statement, MiXED, and ROW! 1. Statement: Each SQL Statement that modifies data is recorded in the binlog. Advantage: you do not need to record changes in each row, which reduces the

Because the system front-end uses the OpenLayers framework, the background database uses Oracle spatial. We all know that the SDO_GEOMETRY of Oracle spatial is very complicated. If you use java APIs for a long time, you will have to deal with a lot

Operating system version: rhel5.5Oracle Client Version: 10g64-bitClient: http://www.oracle.com/technetwork/topics/linuxx86-64soft-092277.html 1. Find the corresponding version, download the following file, and install it. Install basic first, and

Environment: Sys @ ORCL> select * from v $ version;BANNER----------------------------------------------------------------Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-ProdPL/SQL Release 10.2.0.1.0-ProductionCORE 10.2.0.1.0 ProductionTNS

Dynamic listening: When an Oracle instance is started, or the command alter system register is used, or every minute, the PMON process dynamically registers with the listener. the instance_name and service_names parameters in ora dynamically

This problem was found in a test. Restore the backup of the production database on the VM. The server has 24 GB of memory, and the VM has allocated 2 GB of memory. Let's get down to the truth: When the system reports a ORA-00845 error, it is caused

Currently, complex "Hot swappable" systems and Service-Oriented Architecture (SOA) have been widely used, making it increasingly difficult to reasonably integrate data. Although your primary application database runs on the Oracle database, there

In the previous article, three articles mentioned Oracle listening, as follows: Dynamic Registration and static registration of Oracle Listener Description of services in Oracle Listener (Listener) Oracle Database Listener Configuration By default,

RedHat 6.3 source code installation MySQL-5.5.29 details. From MySQL5.5, you need to use cmake to install and so. Here cmake is also used. 1. Install the compilation tool Yum install gcc-c ++ Yum install ncurses-devel Ii. Install cmake and bison 1.