Module 4 - Databases and SQL Flashcards
Cardinality
The relationship that one table can have with another table:
- one-to-one
- many-to-one/one-to-many
- many-to-many
Relational Database origins
The relational database concept was introduced by Dr. Edgar Codd of IBM Research in 1970
Relational database definition
An organized collection of data accessible by electronic means where information type and information relationships are maintained
-OR-
An organized set of related data
Relational Model parts
- Data structure is based on table
- Operators
- Integrity rules
mHealth
The use of mobile devices for health applications
Moore’s law
Intel’s Gordon Moore in 1965 noticed that number of transistors on a chip doubles every 18 months. Many argue that we are reaching the limits of Moore’s law.
ASCII
7 or 8-bit representation of characters (128 or 256 characters)
UTF
Unicode allows the representation of larger character sets than ASCII. It allows 8, 16, or 32-bit representation (UTF-8, UTF-16, UTF-32). Unicode even allows emojis, represented by a single Unicode designation
JPEG
Joint Photographic Experts Group, image compression format.
DBMS
A database management system is a computer program that manages the database and access to it, often using a programming language
Relational DBMS
The relational DBMS links records to tables. For example, we only want to have a single record for the patient, but multiple records for test results. Most query capabilities are based on SQL.
EAV database model
Entity-attribute-value model, aka NoSQL or key-value store.
Metadata types
Descriptive - describes data element for discovery or identification
Structural - describe the organizational structure of data
Administrative - information on how to manage (e.g. who can access and when, how) and preservation (archiving and storage)
Origins of the Internet
It began in the late 1960s as a government project which created a network known as ARPANET capable of securely tying together universities and research organizations.
WWW
World Wide Web was created by Tim Berners-Lee in 1989
Web services
platform-independent, task-specific applications. Implemented via a series of transactions to and from other web-aware applications over a network. RESTful and SOAP
RESTful Services
REST is an architecture, not a standard. Content delivery is typically using XML or JSON
RESTful service components
URI - defines the resource Operation type (GET, DELETE, POST, PUT) MIME (multipurpose internet mail extensions), communicates content type
Database Normalization
The process to reduce redundancy in the data
Primary Key
A primary key is a unique identifier chosen as the key to uniquely identify a row.
Foreign Key
A field or a group of fields in one table that uniquely identifies a row in another table
Attribute, column, field
A database attribute is a column name and the content of the fields under it in a table
Database column
A set of data values of a particular simple type, one value for each row of a database
Database row
A row, or a tuple, represents a single implicitly structured data item in a table. A collection of fields that make up a record.
SOAP
Simple Object Access Protocol. Components are:
- SOAP, an XML based communication protocol
- WSDL (web services description language), describes and locates web services
- UDDI (universal description, discovery, and integration), a directory for storing information about web services. “Yellow pages”
SOA
Service-oriented architecture
