CHAPTER 1 – INTRODUCTION TO ACCESS Akhila Kondai September 30, 2013

INTRODUCTION TO DATABASES A computer database is a structured collection of records or data that is stored in a computer system. A database relies upon software to organize the storage of the data and to enable a person or program to extract desired information. The term "database" refers to the collection of related records, and the software should be referred to as the database management system (DBMS); this is sometimes shortened to database manager or database system.

BUT REALLY WHAT IS A DATABASE? Databases are used in real life, most of you use them without realizing it –WVU Directory – uses databases –Facebook – uses databases –MySpace – uses databases And many more

AN EXAMPLE Let’s look at the WVU Directory page. What you see is sometimes called a form – it is nothing more than a friendly front end interface. Say we want to search for all students named James Smith When you hit search it will run a query that looks like this: SELECT * FROM Students WHERE (((Students.FirstName)="John") AND ((Students.LastName)="Smith"))

AN EXAMPLE – ISOLATING RESULTS WVU has a database somewhere that lists all students, when we do a search we search that database for all students who have a first name James AND a last name Smith. We could either get exactly one result, no results or multiple results. This brings up the question, how do we differentiate between the James Smith that is a History major and the James Smith that is a Radiology major in our database? One way could be to use addresses, since we hope everyone has a “unique” address. But, is there another “unique” identifier that separates one person from another?

AN EXAMPLE – SIMPLE DATABASE In this example we can see why using last name as a “unique” way to identify students maybe a bad idea. StudentID, FirstName, LastName, Major, are called Fields. Each entry is called a Record, a collection of records make up a Table. A collection of tables make up a database. The Field StudentID has a special name called Primary Key since it uniquely identifies each student, no two students can have the same StudentID. Student IDFirstNameLastNameMajor

WHAT IS ACCESS? “Is a relational database management system from Microsoft which combines the relational Microsoft Jet Database Engine with a graphical user interface.” Access is NOT a database – it is a database management system. There are numerous other database management systems. 7

ACCESS VS EXCEL When to use Access? When you need a relational database to store your data or you anticipate adding more tables. When you have a large amount of data Rely on external databases to derive and analyze the data you need Need to maintain constant connectivity to an external database Need to regroup data from different tables in a single place with complex queries Have many people working in the database and need strong options to update the data 8

ACCESS VS EXCEL When to use Excel? Require a flat or non relational view of your data Want to run calculations or statistical comparisons on your data Know your data set is manageable (no more than 15,000 rows) 9

THE HOME TAB HOME Tab – the basic Access tab. Contains basic editing functions such as cut and paste along with most formatting actions. Views Clipboard Font Rich Text Records Sort & Filter Find 10

THE CREATE TAB CREATE Tab – Brings together all create operations in one area. Includes ability to create queries through the wizard or in Design view. Tables Forms Reports Other 11

THE EXTERNAL DATA TAB EXTERNAL DATA Tab – Contains all operations to facilitate collaborations and data exchange. Import Export Collect Data SharePoint Lists 12

THE DATABASE TOOLS TAB DATABASE TOOLS Tab – The area that contains the operational backbone of Access. Here you create and maintain relationships of the database. You also analyze the file performance and perform routine maintanance. Macro Show/Hide Analyze Move Data Database Tools 13

BASIC ELEMENTS OF A DATABASE Field – is a basic entry or a data element, such as the name of a book or the telephone number. A field that uniquely identifies a record is called a Primary Key. Record – is a complete set of all of the data (fields) pertaining to one person, place, etc Table – is a collection of records, every table contains the same fields in the same order Database – consists of one or more tables and the supporting objects used to get data from those tables. 14

ACCESS TABLE EXAMPLE Fields RecordsRecords

COMPARING ACCESS TO EXCEL A FIELD in Access is equivalent to a COLUMN NAME in Excel A RECORD in Access is equivalent to a ROW in Excel A TABLE in Access is equivalent to a WORKSHEET in Excel A DATABASE in Access is equivalent to a WORKBOOK in Excel 16