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Chapter 1
Database Management Systems
45
Computer Science
Undergraduate 2
01/17/2017

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Term
A very large, integrated collection of data. Software package designed to store and manage databases. Provides efficient, reliable, convenient, and safe multi-user storage of and access to massive amounts of persistent data
Definition
Database Management System (DBMS)
Term
A DBMS models real-world _____
Definition
enterprise
Term
DBMS must stage large datasets between _____ _____ and _____ _____, have _____ code for _____ queries, protect data from _____ due to multiple concurrent users, _____ recovery, _____ and _____ control
Definition
main memory, secondary storage, special, different, inconsistency, security, access
Term
Database applications may be programmed via "_____"
Definition
frameworks
Term
Data applications may not use _____ at all
Definition
DBMS
Term
Other data representation
Definition
Excel, XML, JSON
Term
DBMS has data _____ and efficient _____, _____ application development time, data _____ and _____, _____ data administration, _____ access, recovery from _____
Definition
independence, access, reduced, integrity, security, uniform, concurrent, crashes
Term
Shift from _____ to _____. Datasets increasing in _____ and _____. DBMS encompasses most of _____
Definition
computation, information, diversity, volume, CS
Term
collection of concepts for describing data storage form in DBMS
Definition
data model
Term
description of a particular collection of data, using the given data model
Definition
Term
The _____ model of data is the most widely used model today
Definition
relational
Term
basically a table with rows and columns
Definition
relation
Term
Every relation has a _____, which describes the columns, or fields
Definition
schema
Term
_____ schema defines logical structure
Definition
Conceptual
Term
_____ schema describes the files and indexes used
Definition
Physical
Term
Schemas are defined using _____ (_____ _____ _____)
Definition
DDL (Data Definition Language)
Term
Data is modified/queried using _____ (_____ _____ _____)
Definition
DML (Data Manipulation Language)
Term
Steps of Using Database: 1. Design _____ using DDL; 2. Load initial _____; 3. Execute _____ and _____
Definition
schema, data, queries, modification
Term
constructs the database system
Definition
DBMS implementer
Term
establishes schema
Definition
database designer
Term
develop the programs to interact with databases
Definition
database application developer
Term
maintains the databases and loads data
Definition
database administrator
Term
protection from changes in logical structure of data
Definition
logical data independence
Term
protection from changes in physical structure of data
Definition
physical data independence
Term
DBMS users can pretend they are using a _____-_____ system
Definition
single-user
Term
atomic sequence of database actions (reads/writes)
Definition
transaction
Term
Each transaction, executed completely, must leave the DB in a _____ _____ if DB is consistent when the transaction begins
Definition
consistent state
Term
Users can specify some simple _____ _____ on the data, and the DBMS will enforce these constraints
Definition
integrity constraints
Term
DBMS does not really understand the _____ of the data
Definition
semantics
Term
Ensuring that a transaction (run alone) preserves consistency is ultimately the _____ responsibility
Definition
user's
Term
DBMS ensures that execution of {T1, ... , Tn} is equivalent to some _____ execution T1' ... Tn'
Definition
serial
Term
If an action of Ti (say, writing X) affects Tj (which perhaps reads X), one of them, say Ti, will obtain the lock on X first and Tj is forced to wait until Ti completes; this effectiely orders the transactions
Definition
Strict 2PL locking protocol
Term
What if Tj already has a lock on Y and Ti later requests a lock on Y? (_____!) Ti or Tj is _____ and restarted!
Definition
Deadlock, aborted
Term
DBMS ensures _____ (all-or-nothing property) even if system crashes in the middle of a Xact
Definition
atomicity
Term
Keep a _____ (history) of all actions carried out by the DBMS while executing a set of Xacts
Definition
log
Term
Before a change is made to the database, the corresponding log entry is forced to a safe location. OS support for this is often inadequate
Definition
WAL protocol
Term
After a crash, the effects of partially executed transactions are _____ using the log
Definition
undone
Term
The following actions are recorded in the log: Ti _____ an object: the _____ value and the _____ value. Log record must go to disk _____ the changed page!; Ti _____/_____: a log record indicating this action
Definition
writes, old, new, before, commits, aborts
Term
Log records _____ together by Xact ID, so it's easy to undo a specific Xact
Definition
chained
Term
Log is often _____ and _____ on "stable" storage
Definition
duplexed, archived
Term
All log related activities are handled transparently by the _____
Definition
DBMS
Term
Name some people involved in databases
Definition
end users, DBMS vendors, DB application programmers, database administrator (DBA)
Term
Designs logical/physical schemas, handles security and authorization, data availability, crash recovery, database tuning as needs evolve
Definition
database administrator (DBA)
Term
A typical DMBS has a _____ architecture
Definition
layered
Term
Example of a DBMS architecture
Definition
Query Optimization and Execution, Relational Operators, Files and Access Methods, Buffer Management, Disk Space Management
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