Introduction Flashcards
what is a dbms
database management system
software defined to define, manipulate, retrieve and manage data in a database
what is data
meaningful information
what is a database system
DBMS + data
what is SQL
structured query language
manipulates and talks to databases
what are the four categories of SQL instructions
queries, data manipulation, data definition, data control
what is noSQL
does not follow relational DB rules. prone to performance issues
give some DBMS functionality (5)
define database in terms of structures and constraints
construct and load
manipulation: retrieve, modify, access
processing and sharing
give the different abstraction levels of a database
physical - how data is stored logical - what data is stored view - user view
what is logical data modelling
representing data architecture in a graphical way
what are two techniques for logical data modelling
ER
and unified modelling language
what is a database schema
specification of the tables, attributes and relations that make up a database
what is a domain
set of atomic values of a type of data
what 3 sub languages make up SQL
DDL- data definition language
DML- data manipulation language
DQL - data query language
