ICT Database Lesson 1 What is a Database

ICT Database Lesson 1 What is a Database?

Objectives • 9. 1. 1: Describe the functions of a relational database. • 9. 1. 2: Distinguish between databases and spreadsheets. • 9. 1. 3: Identify advantages of using a database instead of alternatives (e. g. , spreadsheets, electronic documents, paper). • 9. 1. 4: Describe real-world uses for databases, including search engines, schools, hospitals, retail. • 9. 2. 10: Identify and compare various database applications, including Microsoft Access, My. SQL, Oracle. • 9. 2. 9: Describe Structured Query Language (SQL) and discuss its use with databases. • 9. 1. 5: Define "big data" and describe how it is used in advertising.

Database A file that stores data in an organized fashion so that information can be retrieved from it. Examples: • i. Pod playlist • Netflix movie list • Contacts in cell phone

Table – Flat-file Database • • A collection of data organized in rows and columns that can be used to store and manage information Work great with small lists of data (information) that is all related. A simple way to create a flat-file database is to use a spreadsheet. Store information in cells created by using columns and rows of data

Spreadsheets - Advantages • • Great for analyzing and sorting related data. Easy to learn and use Suitable for storing and "crunching" relatively small volumes of numerical data. Able to present numerical data in the graphical form to quickly analyze data.

Spreadsheets - Disadvantages • • Require that you enter the same information in multiple places Have simplistic sorting and querying capabilities Contain only a finite number of records Changes to data in the computer memory and are not complete until the file is saved

Data Integrity The validity of the data “Garbage in, garbage out. ” Arizona / ARIZONA / Ariz / ARIZ / Az / AZ.

Creating Tables 1. Identify duplicate data 2. If duplicate data exists, create a separate table just for that data 3. Relate it back to the original table

Relational Database Consists of multiple tables of information related through common fields

Advantages 1. Hold as much as 2 gigabytes of data and are only limited by server operating system. 2. Allows for the simultaneous access and query of data by multiple individuals in multiple locations. 3. Data is protected against inadvertent corruption so you no longer need to keep redundant data. 4. We don’t have to manually enter the information reducing time, effort and mistakes. 5. Entering information is minimalized which reduces input time, resources and opportunities for human error. This reduces cost and increases data integrity. 6. Reduced processing time for large amounts of data.

Disadvantages 1. They are more complex and harder to learn and use than spreadsheets. 2. Designing relational tables can be more difficult and timeconsuming. 3. Software and hardware costs are higher than a spreadsheet.

Database Management Systems A program used to store, access and manipulate database information • Microsoft Access is an end-user DBMS that you can use to create and manipulate fairly small and uncomplicated databases ü Graphical user interface ü Wizard • Oracle, My. SQL, IBM’s DB 2 and Microsoft SQL Server are high-end DBMS programs used to create and manipulate large, complex databases used in large organizations

SQL – Structured Query Language A sub-language commonly used for developing and managing databases • SQL pronounced “sequel” • Used primarily in a database to retrieve, update, insert or remove information • Sufficiently powerful and can create tables, restructure tables and remove tables, among other very complex tasks

ODBC - Open Database Connectivity • An open standard application programming interface (API) • Allows us to use the MS Access interface tools to access the DBMS data. Using a simplified graphical user interface (GUI) like MS Access to build queries and reports is a flexible way for a relative novice to gain access to a wealth of company data.

Big Data A term that describes enormous volumes of data that are too huge for regular database programs • Unlike data in a database, big data is unstructured and unrelated. • Analysis of big data requires specialized tools.