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Introduction to Access. Busn 111 - Intro to Business Computing Edward Mitchell. What is Access?. Access is a “data base” program for storing and retrieving information While you can store data in Excel lists and tables, Access is better for storing large quantities of data
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Introduction to Access • Busn 111 - Intro to Business Computing • Edward Mitchell
What is Access? • Access is a “data base” program for storing and retrieving information • While you can store data in Excel lists and tables, Access is better for storing large quantities of data • Access can store many types of information more efficiently - meaning less storage, less duplication of data
Other kinds of databases • Access is a “relational database” - which for now we will leave as a “fancy name” - but implies a certain kind of flexibility and power unavailable other forms of data storage • Flat-file database - old fashioned library card catalogs, a simple list of information in Excel
Flat File + and - • Flat files are easy to understand and setup • Flat files can be inefficient at storing information (narration covers example of a customer order at an online store) • Duplicated data leads to errors
Relational databases • A relational database stores information in tables • Properly structured, is more efficient and eliminates duplication of data
Relational Example • We have a table containing the customer’s order • Rather than storing the customer information with the order, we store only a unique identifier for the customer (for simplicity, let’s say the phone #) • In a separate Customer table, we store all of other customer information
Relational Example 2 • When the customer places an order, we store the customer’s phone # in the order table with the order. • We use the phone # to cross reference to the Customer table. • For each order, we have only one copy of the Customer contact information
Relational Example 3 • By storing only one copy of the customer data, rather than storing with each order, we use up less disk storage • If the customer moves, we only need to update a single entry in one table. • We do not need to find all previous orders and change those too.
Access “Tables” • Information is stored in “tables” • Think of a table as containing a “record” of related data such as name, address, city, zip, telephone and email address. • A “customer table” then contains a collection of data records, each record having information about one customer
Tables and “records” • The data stored in each “record” is actually contained in “fields”. • For example, “Name”, “Address”, “City”, “State”, “Zip” and “Telephone” are six separate fields to hold each value.
Relationship Concepts • The Customer_Order table • The Customer_Info table • Linked or “related” by a relationship. • Orders are made-by customers • Thus, each order is linked to a customer - in our example, through the phone #.
Multiple Tables • Each access database can contain multiple tables • We could store the Customer_Orders and Customer_Info tables inside the same Access database file
Retrieving Data • We search for data in the tables (database) using a “Query” • A query is - in some ways - similar to the “criteria” we used in Adv Filter in Excel. We use the query to select records that match our query criteria.
Creating a new database • Creating a new database means defining the tables, and the field within each table • It also means defining the “type” of the data that goes in each field • This can require some tedious, detail oriented work to define each field in your table
Using “Wizards” • For many applications, you can use one of Microsoft’s database creation wizards • There are many types of “standard” database designs that you can choose from, and customize • The wizard creates the tables, fields, data definitions for each field and more
Entering and Editing Tables • We can enter and edit data directly in a table • A table “view” looks very much like an Excel worksheet of columns of data
Forms • We can create a “form” for data entry and editing • A “form” is like a dialog box
Intro to Access • This concludes the basic introduction to Access and databases • Next time we will begin some specific exercises to practice creating tables • Homework: Read pages 1259 to 1275 in Chapter 46.