ITUCU » database connectivity

Export and Import for DBAs

Rashmi — Sun, 14 Feb 2010 16:09:10 +0000

The DBA can use additional features of the Export (EXP) and Import (IMP) utilities that a user can use to save and restore database objects.for backing up all user objects in the database or to copy a tablespace to another database. The tablespace copy feature, introduced in Oracle9i, is known as transportable tablespaces. It is [...]

SPFILE in Oracle

Rashmi — Sun, 31 Jan 2010 18:11:14 +0000

An SPFILE (Server Parameter File), new to Oracle9i, is a binary file. The file is not meant to be modified manually and must always reside on the server side. After the file is created it is maintained by the Oracle server. If modified manually, the SPFILE is rendered useless. The SPFILE provides the ability to [...]

PFILE in Oracle

Rashmi — Sun, 31 Jan 2010 17:55:59 +0000

The PFILE (initSID.ora) is a text file that can be maintained using a standard operating system editor. The PFILE is read only during instance startup. If the file is modified, the instance must be shut down and restarted in order to make the new parameter values effective. By default, the PFILE is located in the [...]

Background Processes in Oracle

Rashmi — Sun, 31 Jan 2010 13:34:10 +0000

A process on a server is a section of a computer program in memory that performs a specific task. When the Oracle server starts, multiple processes are started on the server to perform various functions as part of the Oracle instance. While a detailed discussion of all Oracle background processes is beyond the scope of [...]

Initialization Parameter Files in Oracle

Rashmi — Sun, 31 Jan 2010 06:33:40 +0000

In order to start an instance and open the database, you must connect as SYSDBA and enter the STARTUP command. The Oracle server will then read the initialization parameter file and prepare the instance according to the initialization parameters contained within. Note: You must have SYSDBA privilege. Entries are specific to the instance being started [...]

Starting up & Opening of Database in Oracle

Rashmi — Sun, 31 Jan 2010 06:27:31 +0000

Given below are the various commands & steps which are used to startup & open the database for accessing it in Oracle. STARTUP Command Behavior Order of precedence: spfileSID.ora Default SPFILE initSID.ora Default PFILE Specified PFILE can override precedence. STARTUP PFILE = $ORACLE_HOME/dbs/initDBA1.ora PFILE can indicate to use SPFILE. SPFILE = /database/startup/spfileDBA1.ora Starting Up [...]

Process Structures in Oracle

Rashmi — Sat, 30 Jan 2010 06:05:32 +0000

Oracle takes advantage of various types of processes: • User process: Started at the time a database user requests connection to the Oracle server • Server process: Connects to the Oracle instance and is started when a user establishes a session User Process A program that requests interaction with the Oracle server • Must first [...]

Oracle Server Components

Rashmi — Thu, 28 Jan 2010 04:00:50 +0000

An Oracle server consists of both a database and an instance. In Oracle terminology, database refers to only the physical files on disk. These are the files thatstore the data itself, the database state information in the control file, and the changes made to the data in the redo log files. The term instance refers [...]

OCI (Oracle Call Interface)

Rashmi — Wed, 27 Jan 2010 16:52:22 +0000

OCI (Oracle Call Interface) : A set of library routines that allows a C application on virtually any development platform to easily connect to and process SQL statements against an Oracle database. The OCI routines are called as native C library functions; therefore, no preprocessor is necessary when compiling a C application using OCI. OCI [...]

ODBC/JDBC Drivers

Rashmi — Wed, 27 Jan 2010 04:30:08 +0000

ODBC (Open Database Connectivity) : A set of standards that allow applications that are not dependent on any one specific database to process SQL statements against any database that supports SQL Many tools in the Windows (and Unix) environment can take advantage of a common framework known as ODBC, which stands for Open Database Connectivity. [...]