9 Databases Flashcards
Database
A database is a structured collection of data that allows people to extract information according to their specific requirements.
why are database useful
To store data about people, things, and events.
Any modifications or additions need to be made only once, to ensure data consistency.
All users access and utilize the same set of data, promoting uniformity.
Relational databases store data in a non-repetitive manner, eliminating duplication.
record
– a collection of fields that describe one item (row)
table
– a collection of related records in a database
field
– a database table (colum)
data type
a classification of how data is stored and displayed, and of which operations that can be performed on the stored value
Text/Alphanumeric
This data type allows letters, special characters like spaces and punctuation and numbers to be entered into a field ex NG321AE
Character
This allows single characters to be entered into a field. Characters can be any alphanumeric value and can be lowercase or uppercase ex A
Boolean
This data type can be used in fields where there are only two possible options ex True/False
Integer
Only whole numbers can be entered
real
Numbers including decimal numbers can be stored
Date/Time
basically Date/Time
primary key
Each table has a primary key field which acts as a unique identifier It does not contain any duplicate data items
how sound files are compressed using lossless compression
compression algorithm is used
no data will be removed
example of type of algorithm that would be used e.g RLE
repeated patterns in the music are i identified and indexed
