Databases Reference
In-Depth Information
Protocol
Rules defining data format and transmission enabling computers to
communicate.
Proxy server
Support server that, among other functions, can cache copies of recently
retrieved Web pages.
Public
SQL Server database role to which all database users belong.
Publicity
Informing potential users about available data and database structure.
Qualifying conditions
See search argument.
Query cache
Area of dedicated memory associated with the Web server that is used to
temporarily hold query results.
Query mode
Interactive mode of SQL statement execution.
Query optimizer
See query processor.
Query processor
DBMS component responsible for parsing, optimizing, and compiling
queries for execution. Also known as a query optimizer.
Query
Executable statement written in a DBMS language and typically used to retrieve
or manipulate data.
RAID
Redundant Array or Inexpensive (or Independent) Disks, disk configurations
commonly used with database systems that provide enhanced performance and, in most
configurations, fault tolerance.
Read committed
Transaction isolation level that prevents dirty reads by not reading
uncommitted data.
Read uncommitted
Least restrictive isolation level that does not acquire locks and
ignores exclusive locks during reads.
Recovery
The process of updating database tables based on committed transactions
in the transaction log.
Referenced entity
The entity to which another entity refers in a relationship.
Referencing entity
The entity which refers to and is associated with another entity in
a relationship.
Referential integrity
Another name for relational integrity, referring to the fact that
you are maintaining the relationship between referencing and referenced tables.
Relational database
Database based on the relational model.
Relational database model
Database model based on entities that are associated with
each other through relationships.
Relational integrity
Ensuring that relationships between tables are correctly created
and maintained.
Relational result
See result set.
Relationship
An association defined and established between two data entities.
Removable media
Media that can be physically removed from the computer.
