Index:
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
 

Connection Manager

Concentrates multiple clients into a single multiplexed data connection.

Connection Pooling

Places idle users in suspended mode and reassigns their physical connections until they become active.

Common Object Request Broker Architecture.  An architecture that enables pieces of programs called "objects" to communicate with one another regardless of programming language implemented in or operating system they are running on.

DBMS

Database Management System.  Synonym with the term Database System and often used in place of the term Database.  It is technically the software product that manages a database.

Set of contiguous operating-system blocks.  In Oracle, smallest until of data storage and can not span data files.

Collection of tables that store info about database objects such as tables, views, etc. In Oracle, these tables are owned by SYS and created at database creation..

Built on data dictionary tables.  Used to query the data dictionary.  Recall views are stored SQL statements.

Database Administrator.  Person that installs, creates, maintains a database.

DDL

Data Definition Language.  Used to create the structure of a database.  For example the SQL command used to create a table (create table).

DML

Data Manipulation Language.  Represents how you do things like inserts, deletes in databases.

Data Mart

Similar to Data Warehouse but, usually used to integrate departmental or workgroup databases instead of Enterprise databases

Data Warehouse

A data store containing information that can be used by various smaller operational databases.

Used in distributed database environment to access remote database objects.

Extents

A collection of contigous data blocks that can not span data files.  Oracle allocates space in terms of number of extents.

A foreign key is a column or set of columns whose values serve as primary keys in some other relational table.  It should be NULL or should match exactly the primary key value of some other table it references.

Used to store table data by applying a hash function to the primary key values of the table.  The has function is applied to the key value being requested and the result is used to obtain the Oracle data block in the hash cluster.

IIOP

Internet Inter-ORB Protocol.  A protocol developed by the Object Management Group (OMG) to implement CORBA solutions over the WWW.  IIOP enables browsers and servers to exchange integers, arrays and more complex objects, unlike HTTP, which only supports transmission of text.

Indexes

Data segments that are used to speed up retrieval of data from tables.  Consist of one or more columns of a table and the ROWID for corresponding column values.

Metadata

Data that provides information about the stored data such as name, location and type of data.

OCI

Oracle Cal Interface.  Protocol implemented in C/C++ to make calls to access the database

Primary Key

A column or set of columns whose values are used to uniquely identify rows (records) in a relational table.  A primary key consisting of multiple columns are referred to as composit or concatenated keys.  Can not be null or empty, nor duplicates..

Database where data is stored in tables and manipulated through the use of mathematically defined relations.

Responsible for providing read-consistency.  Store before-state of data that is changed by transactions but, not yet committed.

Segment

Chain of extents allocated for a specific database object such as a table.  Segments CAN span data files, as they are non-contigous.
 

Snapshot

In Oracle, this is a report on the current state of the database.

Synonyms

Used as pointers to other database tables.  This is really the same as the common use of this word in English.  In Oracle, you can have public or private synonyms....see on-line or reading material.

Table Clusters

Database object that physically stores groups of tables within the same data block.  Can be used to improve I/O performance when the tables comprising the cluster are used together.

Stored units of code that perform some task on a table.  They are different from stored procedures in that they are automatically fired when certain events occur.  This event may be an insert, update or delet or any combintation of these on a table.  Triggers can be fired for each row or statement.  In Oracle:  you can use the data dictionary view dba_triggers to obtain information abou triggers.

Stored SQL statements that are used to customize retrieval of information.   They are good because they can hide distributed data.

VLDB

Very Large Database.