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The relationship (within the relation) that describes how the value of one
attribute may be used to find the value of another attribute.
ANSWER:<< Functional Dependency
An attribute that can be used to find the value of another attribute in the relation.
ANSWER:<< Determinant
Value can be used to find the value of every other non-key attribute in the table.
Unique and minimal.
ANSWER:<< Candidate Key
Reads blocks directly, without accessing an index.
ANSWER:<< Table Scan
Reads index blocks sequentially in order to locate the needed table blocks.
ANSWER:<< Index Scan
Database repeatedly splits the index in two until it finds a match.
ANSWER:<< Binary Search
Database object that maps one or more tables to a single file.
ANSWER:<< Tablespace
Specifies tables, columns, and keys. Implements database requirements in a
specific database system. Also called a schema.
ANSWER:<< Logical Design
Define & manage database structures
,ANSWER:<< DDL
Adding, deleting, and modifying data - Manipulates data stored in a database.
ANSWER:<< DML
Used to create user accounts, manage permissions and access.
ANSWER:<< DCL
Includes CREATE, DROP, ALTER, TRUNCATE, RENAME
ANSWER:<< DDL
A view created and stored on the database. Underlying data is changed and also
updated in this view. Uses memory space.
ANSWER:<< Materialized View
Not stored in memory. Only computed when used or accessed.
ANSWER:<< Virtual View
The data about the data. Describes elements such as columns, names, and data
type.
ANSWER:<< Metadata
Ordered collection of elements in parentheses.
ANSWER:<< Tuple
% of table rows selected by a query
ANSWER:<< Hit Ration
Specifies indexes, table structures, and partitions. Specifies how tables are
organized on storage media.
ANSWER:<< Physical Design
Components of a computer system and the relationships between components.
ANSWER:<< Architecture
Interact directly with database users and administrators and send queries to the
query processor. Includes Connectors & APIs, Workbench, and utility programs.
ANSWER:<< Tools
,Interprets queries. Compiles queries into low-level instructions for the storage
engine. Creates a plan to modify the database or retrieve data, and returns
query results to the application.
ANSWER:<< Query Processor
Link between tools and query processor
ANSWER:<< Connection
Creates connections and manages communication between tools and query
parser.
ANSWER:<< Connection Manager
Translates the query processor instructions into low-level file system commands
that modify or retrieve data.
ANSWER:<< Storage Engine
Accesses data on storage media. Data stored on storage media and organized
in files. Contains 3 types of data: - User data (tables & indexes) - Log files
(record of any changes) - Data dictionary (aka: catalog directory of tables,
columns, keys, indexes in a relational database). One row for each database
object.
ANSWER:<< File System
Stores reusable information in main memory.
ANSWER:<< Cache Manager
Retains data blocks from the file system for possible reuse.
ANSWER:<< Buffer Manager
Arranged in hierarchy
ANSWER:<< Multi-tier architecture
Multi-tier consisting of web browsers and web servers communicating over the
internet.
ANSWER:<< Web architecture
A software layer that emulates a complete, independent computing
environment.
ANSWER:<< Virtual Machine
, A database offered as a PaaS cloud service.
ANSWER:<< Cloud Database
A statement or proposition from which another statement is inferred.
ANSWER:<< Premise
Multiple processors managed by a single operating system instance.
Shared memory - share the same memory and storage media.
Shared storage - share storage media only.
Shared nothing
ANSWER:<< Parallel Computer
Group of computers connected by LAN or WAN
ANSWER:<< Node
Group of nodes connected by a LAN, managed by separate operating system
instances. Similar to a parallel computer.
ANSWER:<< Cluster
Runs on a parallel computer or cluster
ANSWER:<< Parallel Database
Runs on multiple computers connected by a WAN
ANSWER:<< Distributed Database
Updates data on multiple nodes of a distributed database. Two-phase commit
(nodes receive notice of update, store update in log, send confirmation, then
receive commit). Either all nodes or no nodes must be successfully updated.
ANSWER:<< Distributed Transactions
Updates data on a single node of a distributed database. Databases that use this
are called "eventually consistent".
ANSWER:<< Local Transaction
States that a distributed database cannot be Consistent, Available, and Petition-
tolerant simutaneously. Availability refers to individual nodes. Consistent
database - confirms to all rules at all times. Network partition - forms when a
network error prevents nodes from communicating. Petition-tolerant - database
that continues to function when a network partition occurs.