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ORACLE OVERVIEW


Oracle is a multi-user database management system - A software package specializing in managing a single, shared set of information among many concurrent users. Oracle is one of many database servers that can be plugged into a client/server equation. Oracle works to efficiently manage its resource, a database of information, among the multiple clients requesting and sending dta in the network.

Oracle has many important freatures that make it not only an exceptional database management system, but also an excellent database server choice for client/server computing. Oracle supports all major operating systems for both clients and servers, including MSDOS, NetWare, UnixWare, OS/2 and most Unix flavors. Oracle networking software, SQL*Net, also supports all major network communication protocols, including TCP/IP, SPX/IPX, Named Pipes and DEC-Net. Therefore, Oracle can be the link which joins the many data stores and networks throughout the heterogeneous computing systems prevalent in most corporations.


FREQUENTLY ASKED QUESTIONS:


WHAT IS A TABLESPACE?

A Tablespace is a logical portion of an ORACLE database used to allocate storage for table and index data. Each tablespace corresponds to one or more physical database files. Every ORACLE database has a tablespace called SYSTEM and may have additional tablespaces. A tablespace is used to group related logical structures together. For example, tablespaces commonly group all of an application's objects to simplify certain administrative operations.
As there will likely be many client applicatons which access a database in your client/server system, it is best to create one or more Tablespaces to hold each application's data separate from the data dictionary and the data of other applications.
NOTE: Tablespaces are, for the most part, a DBA type of storage issue. Therefore, you will likely not need to address them in troubleshooting VB/Oracle support calls.
You may, however, encounter situations where the Owner of a table must be identified in order to access the table.
For example:

OwnerName.TableName


WHAT IS A PACKAGE?

Packages are a method of encapsulating and storing related procedures, functions, and other package constructs together as a unit in the database. While packages provide the database administrator or application developer organizational benefits, they also offer increased functionality and database performance.
Calling a public procedure or function that is part of a package is no different than calling a stand-alone procedure or function, except that you must include the program's package name as a prefix to the program name.
For example:

PackageName.Function/ProcedureName

NOTE: When using Packages, if there is a specific Owner to a procedure or function contained within a Package, you would call the procedure as follows:

OwnerName.PackageName.ProcedureName.

WHAT IS A SCHEMA?

A Schema is a collection of table definitions or related objects owned by one person or user. "Scott" is a Schema in the ORCL database. Schema objects are the logical structures that directly refer to the database's data. Schema objects include such structures as tables, views, sequences, stored procedures, synonyms, indexes, clusters, and database links.
NOTE: There is no relationship between a tablespace and a schema: objects in the same schema can be in different tablespaces, and a tablespace can hold objects from different schemas.


WHAT IS SQL PLUS?

SQL Plus is the front end tool for Oracle. The SQL Plus window looks much like a DOS window with a white background similar to Notepad. This tool allows you to type in your statements, etc. and see the results. For instance, you can create tables, stored procedures, etc. as well as issue a SQL Select Statement here and have the results presented in this same window as well.
ITEMS TO NOTE: Unlike some other editors, it is not a simple task to go back and edit items once they have been typed in this window. For example, if you are on the same line in which you'd like to change your code, it is necessary to backspace and erase all items leading back to where you'd like to make your change. Also, once you are on the next line in your code, you are not able to go back to the previous line to make changes, etc. It is not possible to place the mouse at a given point and edit accordingly. Once you hit enter or execute what you've typed, if you receive an error and/or realize that changes are necessary, you may type the word "Edit" and then enter. SQL Plus will then present a version of Notepad which will contain the text of the most recent statement you input in the SQL Plus Window. You can, in this Notepad Window, make your desired changes. When the changes are complete, simply close the Notepad window. You will be presented with a message box asking if you'd like to save the changes. By confirming 'Yes', the text will be copied from Notepad back into the SQL Plus window to be executed. The only problem, though, is that the Notepad text is not saved. If you wish, once again, to make additional changes, you must follow the same procedure.
TIP: Therefore, my recommendation is to open a separate instance of Notepad and have it running minimized. I will type my script(s) into Notepad and simply copy each statement into the SQL Plus window to be executed. This way, I can save all of my scripts in a text file separately from SQL Plus which affords me the ability to go back and use those same scripts at will.


WHAT IS SQL*NET?

This is Oracle's own middleware product which runs on both the client and server to hide the complexity of the network.
SQL*Net's multiprotocol interchange allows client/server connections to span multiple communication protocols without the need for bridges and routers, etc. SQL*Net will work with any configuration design.


WHAT IS SQL*LOADER?

A utility used to load data from external files into Oracle tables. It can load data from an ASCII Fixed-Format or delimited file into an Oracle table.


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