Intro to Comp Sci Chapter 12

information system

software that helps the user organize and analyze data.

spreadsheet

a program that allows the user to organize and analyze data using a grid of cells.

cell

An element of a spreadsheet that can contain data or a formula.

data stored in a cell can be

text, numbers, or “special” data such as dates

spreadsheet function

A computation provided by the spreadsheet software that can be incorporated into formulas.

range

a set of contiguous cells specified by the endpoints.

A circular reference

a set of formulas that ultimately, and erroneously, rely on each other to compute their results.

A what-if analysis

Modifying spreadsheet values that represent assumptions to see how changes in those assumptions affect related data.

database

a structured set of data; Data structured in a logical form

database management system (DBMS)

a combination of software (key components of a database) and data made up of the physical database, the database engine, and the database schema.

Physical Database

the collection of files that contain the data.

database query

A request to retrieve data from a database.

database schema

a specification of the logical structure of data in a database; not physical, but laid out logically; shows users how they relate to one another.

Database Engine

a software that supports access to and modification of the database contents.

A relational model

a database model in which data and the relationships among them are organized into tables.

Tables

a collection of database records.

Records (or object, or entity)

a collection of related fields that make up a single database entry. 

Field(attributes)

a single value in a database record; lowest level of a database system

Record Key

one or more fields of a database record that uniquely identify it among all other records in the table.

Structured Query Language

a comprehensive relational database language for data management and queries.

Entity-relationship (ER) modeling

 A popular technique for designing relational databases.

ER diagram

a graphical representation of an ER model; Important information of record types, attributes and relationships and puts it in a graphical form making it easy to read)

cardinality constraint

the number of relationships that may exist at one time among entities in an ER diagram.

important part of ER diagram

cardinality constraint

cardinality constraints

Either 1:1, 1 : many, many:many relationship

Electronic commerce

the process of buying and selling products and services using the World Wide Web.; ex: Ebay, Amazon

Cryptocurrency

digital currency used for financial transactions without government backing or institutional intermediaries.

Digital Wallet

used to conduct transactions using cryptocurrency

Non-Fungible Token (NFT)

a certificate of authenticity for digital assets such as art

blockchain

an incorruptible public ledger of transactions.

block

a record of new transactions. Once verified using established algorithms and encryption technology, creates new transaction is added to a block, and the block is added to the chain of ongoing sequential transactions

big data

 large data sets that defy conventional management (too large) solutions such as spreadsheets and databases.

benefits to big data

numerous for business, health care, law enforcement, and public safety

challenges to big data

• Large data sets, including multimedia elements

• Memory space needed (not only images, but also videos)

• Organizing and analyzing the data so that it can be used effectively (into a product)

• Protecting the data

SUM(val1, val2 …) / SUM(range)

sum of specified set of values

COUNT(val1, val2, …) , COUNT(range)

count of the number of cells that contain values

MAX(val1, val2, …) / MAX(range)

largest value from the specified set of values

SIN(angle)

The sine of the specified angle

PI()

The value of pi

STDEV(val1, val2, ..) / STDEV(range)

The standard deviation from the specified sample values

TODAY()

Today’s date

LEFT(text, num_chars)

The leftmost characters from the specified text

IF(test, true_val, false_val)

If the test is true, it returns the true_val; otherwise, it returns the false_val

ISBLANK(value)

Returns true if the specified value refers to an empty cell