Introduction to an Oracle Instance

Every running Oracle database is associated with an Oracle instance. When a database is started on a database server (regardless of the type of computer), Oracle allocates a memory area called the System Global Area (SGA) and starts one or more Oracle processes. This combination of the SGA and the Oracle processes is called an Oracle instance. The memory and processes of an instance manage the associated database's data efficiently and serve the one or multiple users of the database.

An instance is the (executed) Oracle software (Oracle processes) and the memory they use (SGA). It is the instance that manipulates the data stored in the database. An instance is identified by using methods specific to each operating system. The instance can open and use only one database at a time.

Related Post:-

• Instance Memory Structure 
• Background Process
• Initialization Parameter Files 

Read More

Database Management System (DBMS)

DBMS means "Database Management System."A DBMS is a set of software programs that controls the system organization, storage, management, and retrieval of data in a database. DBMSs are categorized according to their data structures or types. The DBMS accepts requests for data from an application program and instructs the operating system to transfer the appropriate data. The queries and responses must be submitted and received according to a format that conforms to one or more applicable protocols. When a DBMS is used, information systems can be changed more easily as the organization's information requirements change.A DBMS allows different user application programs to concurrently access the same database. DBMSs may use a variety of database models, such as the relational model or object model, to conveniently describe and support applications.

Well known DBMSs include Oracle, IBM DB2, Microsoft SQL Server, PostgreSQL, MySQL and SQLite. A database is not generally portable across different DBMS, but different DBMSs can inter-operate to some degree by using standards like SQL and ODBC to support together a single application. A DBMS also needs to provide effective run-time execution to properly support (e.g., in terms of performance, availability, and security) as many end-users as needed.

Many DBA's think that RDBMS is a Client Server Database system but thats not the case with RDBMS.

Yes you can say DBMS does not impose any constraints or security with regard to data manipulation it is user or the programmer responsibility to ensure the ACID PROPERTY of the database whereas the rdbms is more with this regard bcz rdbms define the integrity constraint for the purpose of holding ACID PROPERTY.

Read More

What is Database

A database is a collection of information that is organized so that it can easily be accessed, managed, and updated.Databases are designed to offer an organized mechanism for storing, managing and retrieving information. They do so through the use of tables.It allows organizations to conveniently develop databases for various applications by database administrators (DBAs) and other specialists.The term "database" may be narrowed to specify particular aspects of organized collection of data and may refer to the logical database, to physical database as data content in computer data storage or to many other database sub-definitions.The term database is correctly applied to the data and their supporting data structures, and not to the database management system (referred to by the acronym DBMS). The database data collection with DBMS is called a database system.The utilization of databases is now spread to such a wide degree that virtually every technology and product relies on databases and DBMSs for its development and commercialization, or even may have such embedded in it. Also, organizations and companies, from small to large, heavily depend on databases for their operations

Read More

Form

In session the first thing that you see is Form. Form is used as an interface between user and table where his data id stored.Form is used to get input

Read More

Session in ERP

Q) why we create session?

Ans This is the most basic question that why we create session. See data is stored in tables, so to manipulate the data which is stored in tables we use sessions. Session is used to add data into tables, we can delete the data from tables. For these purpose we have different kinds of session or we can say types of session:

1)Maintain Session

2)Update Session

3)Print Session

4)Display Session

5)Graph Session

6)Conversion Session

Read More

Form Types

Form has baically four types:

1)Single occurrence(with one main table): Form is used to display only one record of a table.This kind of form is used mainly in maintain and display session.

2)Multi-occurrence(with one main table): Form displays more than one record of a table.This kind of form is used mainly in maintain and display session.

3)Multi-occurrence (with one main table) having some common filed: It is very similar to type-2 form but in this form type there will be some  common field(s) to which all the records will belong. For example Maintain Production BOM session.

4)Single occuerrence(Without main table): In this type of form data daoes not come from single table but it comes from more than table.Print session is an example of this.

Read More

ERP Basic

ERP(Enterprise Resource Planning) is basically an integrated software used to collect internal and external information so that an enterprise can run in a safe mode.ERP has Package for every department of an enterprise like:Distribution package which handles the distribution of items across the industary.

Read More