Database Administrator

Precautions for copying an Oracle database The number of files in the production database copied this time is 9.18 TB, the actual size of the allocated data is 5.16 TB, and the size of the data after compression and backup using RMAN is 1.1 TB. The

Archive mode: Restores data files that are not backed up. Scenario: 1. Open archiving for databases; 2. All archived logs after data files are created are online; 3. Data Files Or tablespaces have not been backed up, databases have not been backed

Oracle session and connection Optimization 1. Modify the Oracle session and maximum number of connections 1. view the maximum number of connections SQL> show parameter processes; NAME TYPE VALUE--------------------------------------------------------

Enable Oracle startup in CentOS 6.4 Objective: To enable Oracle to start on CentOS 6.4 Solution: First add start, close, restart Oracle services and instance services, and then add this service to the System Service running level. Set CentOS to

How can I avoid resetlogs from opening the database after the control file is restored? After the control file is restored, the database is opened using resetlogs, and the sequence of online logs is reset. SYS @ practice> select group #, sequence #,

Database backup and restoration, log cleanup code, and database backup logs -- The database is occupied and cannot be restored. Solution: -- 1. Set the database to work in single-user mode. -- Setting method: Right-click the database to be restored,

DbVisualizer Personal: a common solution to Chinese Garbled text, dbvisualizerIn SQL Commander, if the SQL statement contains Chinese characters, the display is a port. The solution is as follows: In Tools> Tool Properties> General> Appearance>

MySQL database can be accessed using any ip address. Use the CMD command line to modify the value of a field in the database table for connection and access. Step 1. Find the bin directory where the MYSQL software is installed; (1) cd \ Current

Connect to a PDB of Oracle12c, pdboracle12cStory about CDB and PDB Oracle12c has a new feature and definition of CDB and PDB. if you first use 12c you will get confused like me. so that is necessary to know some basic definitions before you start.

[MongoDB] The description of procedure in MongoDB, mongodbdescription In this blog the procedure of mongodb will be described in details. it is known that mongodb has provided a series of efficient solution to some different questions, such as high

The usage of Aggregate functions count, max, min, sum, avg, and NVL in oracle,Usage of Aggregate functions count, max, min, sum, avg, and NVL in oracle The grouping function aggregate function performs computation on a column in a group of rows and

Tablespace (upper), tablespace ( 4. directly modify the tablespace resizing:(1) General tablespace:Automatic Scaling: alter database datafile '/oracle/app/oradata/tbs_sys_ptcl.dbf' autoextend on;Disable auto Scaling: alter database datafile '/oracle/

Configure hugepage and linuxhugepage in Linux For Oracle database servers with large memory, it is necessary to configure HugePage. The following describes how to configure Huge: My environment: OS: CentOS release 6.4 (Final) Oracle: 11.2.0.4 RAC1.

Hibernate Persistence principlesPersistence java classes must follow the following principles:1. This class usually requires an id. We recommend that you use the encapsulation type.2. This class cannot be modified by final.3. You need to provide a

Which of the following is the most common number in 2 billion ?, About 2 billion Baidu, an asshole, swallowed several answers. So I sent it here: 1536 Here I will post some evaluation data. Why? Because I ran on many computers, I lost some of them,

Error: ActiveRecord: IrreversibleMigration exception, exceptionalRecently, the field of the database table was modified in rails3.2 and you want to roll back and cancel the operation. However, when you run the rake db: rollback command, an error

Oracle job, oracleEnable the specified job:BEGINDbms_auto_task_admin.enable (Client_name => 'SQL tuning advisor ',Peration => NULL,Window_name => 'Monday _ window ');END;/How to Create a job in oracle Replace the following stored procedure name with

Oracle foreign key constraint child table, parent table, oracle Constraint Create table employees (Employee_id NUMBER (6 ),Last_name VARCHAR2 (25) not null,Email VARCHAR2 (25 ),Salary NUMBER (8, 2 ),Commission_pct NUMBER (2, 2 ),Hire_date date not

MongoDB operation manual CRUD update, mongodbcrud Modify recordOverview MongoDB provides the update () method for updating records. This method accepts the following parameters: An update condition JSON object is used to match records, an update

Sqlserver locate SQL statements with high resource consumption, and sqlserver locate SQL statements SQL Server views the SQL statements that consume resources, as follows: You can use SQL to quickly locate the CPU in the database, with high IO