"Databases and Data Management" by Alex

data

Streams of raw facts.

information

Data that has been shaped into a meaningful form.

common data integrity problems

Data redundancy, inconsistency, poor security, lack of sharing, and program-data dependence.

database

A group of related tables (files).

table (file)

A group of related rows (records).

row (record)

A group of related columns (fields).

column (field)

Contains characters, words, numbers—represents one data attribute.

entity

A person, place, or thing on which we store information.

attribute

A specific characteristic or quality that describes an entity.

DBMS

A Database Management System is software used to create, process, and manage databases.

functions of a DBMS

Data definition, data dictionary, querying, and reporting.

key field

A field used to uniquely identify each record.

primary key

A field in a table used as a unique identifier.

foreign key

A primary key used in a second table to establish relationships.

normalization

Streamlines complex data groupings to eliminate redundancy and awkward relationships.

referential integrity

Set of rules in RDBMS to ensure consistency in relationships between tables.

entity-relationship diagram

A visual model of entities and their relationships in a database.

poorly designed tables

Causes data integrity issues and inconsistency.

benefit of normalized tables

They eliminate integrity problems and redundancy.

fact table

A central table in a star schema of a data warehouse.

dimension table

A structure that categorizes facts and measures in order to enable users to answer business questions.

Excel as a simple DBMS

Each worksheet is a table; VLOOKUP is used for relational referencing.

cardinality

Describes the number of relationships between data entities (e.g., one-to-many).

four main operations in a DBMS

Read, Insert, Modify, Delete.

SQL

Structured Query Language, used to manage and query data.

SELECT in SQL

Specifies which fields to return.

FROM in SQL

Specifies the source tables.

WHERE in SQL

Sets conditions for data retrieval.

AND/OR in SQL

Combine multiple conditions in queries.

ORDER BY in SQL

Sorts query results by specified fields.

big data

Massive sets of unstructured or semi-structured data from sources like web traffic and social media.

data warehouse

A central repository for current and historical data used for analysis and reporting.

data mart

A subset of a data warehouse focused on a single business line.

Hadoop

An open-source framework for distributed storage and processing of big data.

in-memory computing

Stores data in RAM for rapid access and processing.

analytic platforms

High-speed platforms optimized for analyzing large datasets using both relational and non-relational tools.

OLAP

Online Analytical Processing for multidimensional data analysis.

data mining

Discovering hidden patterns and relationships in large datasets.

text mining

Extracting key elements from unstructured text data.

web mining

Analyzing web content, structure, and usage to gain insights.