GLOSSARY - Introduction to Database Management - page 456

Interactive SQL Statements executed directly through an interactive user interface,
such as a command prompt, for immediate execution on the database server.
Intersection data Data that is part of a many-to-many relationship and associated
with a specific, unique instance of related entities.

Isolation Referring to the fact that a transaction must appear as though it executed by
itself without interference from any other concurrent transaction.

Join A query combining columns from two or more data sources.
Joining Combining the data from two tables based on linking columns.

Key column Column used to define index sort order.

Keyword A part of a command identifying a clause to either supply parameters or
define command actions.

Kill Exit a process without completing any open transactions.
Large object data Data requiring a large amount of storage space.

Latency The time between when data changes and when the change is replicated to
the destination servers.

Leaf node A node located at the lowest level of an index and representing the

actual data.
Local area network (LAN) An arrangement of personal computers connected
together by communication lines.

Local autonomy Delegated responsibility for database server security, backup, recovery,
and concurrency control.

Local variable Object used to store a value in memory temporarily.

Localized management with central oversight Management model with local auton-
omy that includes centralized management control over management decisions.
Lock level

The level at which a lock is acquired, typically database, table, or row.

Lock A restriction placed on access to database objects.

Lock scope See lock level.
Logical design Design process that includes identifying entities and describing the

data model.

Login Security principal used to manage server access and server-level security.

Login credentials Information identifying a user to the database server and used to
set server access permissions.

Lost update A condition where one transaction overwrites another transaction's
changes, causing the first transaction's updates to be lost.
Main memory

Provides temporary storage of data and programs.

Maintenance plan A defined set of maintenance tasks executing on a periodic schedule.
Management model with local autonomy that includes centralized management control
having the final say over management decisions.