BA271 Week 6 Lecture Database Overview Dave Sullivan

Goal for today… Status Report – Review where we are … Status Report – Review where we are … Website / Peer review update Website / Peer review update Compare using Microsoft Access with large corporate databases Compare using Microsoft Access with large corporate databases Look closely at how a multi-table Access database functions Look closely at how a multi-table Access database functions

Access versus large databases … Like a car versus a bus or train … Like a car versus a bus or train … Databases are inherently multiuser systems Databases are inherently multiuser systems Large databases make poor learning tools -- but have lots of specialized features for robust professional users Large databases make poor learning tools -- but have lots of specialized features for robust professional users

A sample Access database Nwind.mdb, a database for the NorthWind Traders company Nwind.mdb, a database for the NorthWind Traders company

Define some key Access terminology Field – A single characteristic or attribute of a person, place, object, event, or idea. Field – A single characteristic or attribute of a person, place, object, event, or idea. Record – A set of related field values. Record – A set of related field values. Table – A collection of records that identify a category of data, such as Customers, Orders, or Inventory. Table – A collection of records that identify a category of data, such as Customers, Orders, or Inventory.

Fieldsrecordsrecords table Fields are grouped into records, and records are grouped into a table. Illustration of fields, records and a table

Relational database and keys A relational database is a collection of tables that are related to one another based on a common field. A relational database is a collection of tables that are related to one another based on a common field. A field, or a collection of fields, is designated as the primary key. A field, or a collection of fields, is designated as the primary key. –The primary key uniquely identifies a record in the table. When the primary key of one table is represented in a second table to form a relationship, it is called a foreign key. When the primary key of one table is represented in a second table to form a relationship, it is called a foreign key.

Relating tables using a common field The primary key in the Employer table (EmployerID) is the common field that relates this table to the Position table. PositionID is the primary key in the Position table. The EmployerID field is a foreign key in this table. Primary keys can only have one occurrence in a table. Foreign keys may have multiple occurrences.

Microsoft Access Assignments Microsoft Access Assignments Tutorial 1 – Introduction To Microsoft Access 2003 Tutorial 1 – Introduction To Microsoft Access 2003 Tutorial 2 -- Creating and Maintaining a Database Tutorial 2 -- Creating and Maintaining a Database Assignment 1: Creating a Database Assignment 1: Creating a Database

Activities you should do: Adjust your website based on what you learned from your Peer Reviews. Adjust your website based on what you learned from your Peer Reviews. Complete Access Assignment #1. Complete Access Assignment #1.Access Assignment #1Access Assignment #1

End of presentation for Winter ‘06

The components of the Access and Database windows

Use the Objects bar to view database objects Queries category The Queries category has been selected, and a query named Contacts is shown in the window. category Objects bar To see a list of objects in a category, click that category on the Objects bar. create new You can also create new objects within each object category.

The Database window Database window The Database window is the main control center for working with an Access database. menu bar The Database window contains a menu bar, an objects bar, and a groups bar. – Objects bar –The Objects bar lists all the objects available in the database – tablesqueries formsreportspagesmacros modules. –The list of objects consists of tables, queries, forms, reports, pages, macros, and modules. – –You can click on any of the objects in the Objects bar to obtain a list of objects of that type

A table in datasheet view

The navigation bar buttons

Learn how Access saves a database Save button The Save button in Access differs from the Save button in other Windows programs. saving the design of the Access objects and NOT the data itself. When you press the Save button in Access, you are saving the design of the Access objects and NOT the data itself. – –Access saves data as it is entered database must always be accessible For this reason, the location at which you are storing your database must always be accessible while working with a particular database. – –If the database is located on a diskette, the diskette must be in the diskette drive at all times while working with this particular database

Sample Query Datasheet view display fields in any order in a query Query Datasheet view looks very similar to Table view. However, the data displayed in a query does not have to be in the same sequence as it appears in table view. You can display fields in any order in a query.

What is an Access query? If you want to see just a portion of the data in a table you can create a query. query A query is a question you ask about the data stored in a database table. Access responds by displaying the data according to your question. – –For example, if you ask to see all the customers from New York, the response would be to display only the records whose state field matches with NY

Open an existing query and create new queries open an existing query You can open an existing query by clicking Queries on the Objects bar and then selecting the query you want to open. create your own queries You can also create your own queries by clicking New on the Database window. Simple Query Wizard To create a new query, you can use the Simple Query Wizard, which will bring you through the selections you want for your query.

Navigating a query and sorting the results sorting the datasheet When you run and get the results of your query, you can reorganize the data by sorting the datasheet in either ascending or descending order. – –Click the pointer anywhere in the column you wish to sort – –Click the Sort Ascending or Sort Descending buttons on the Query Datasheet toolbar to sort the results in the desired sequence navigation buttons You can navigate through the records by using the navigation buttons on the Navigations toolbar.

The Simple Query Wizard The Simple Query Wizard assists you in the creation of a new query.

Selecting fields to include in a query display only selected fields You can create a query that will display only selected fields from a table instead of displaying all fields. Simple Query Wizard In the Simple Query Wizard dialog box, select which fields you want included in the query. – –Move all the fields into the Selected Fields box – –Move the fields one at a time – –Remove fields out of the Selected Fields box by pressing one of the remove buttons remove the one field If you wanted to select all the fields except one, you can move them all to the selected fields list and then remove the one field you don't want. Once you have made your selections, press Next to move to the next dialog box in the Wizard.

Access Form View The navigation bar has the same buttons seen in Table and Query Datasheet view. Forms display one Table or Query record at a time.

Create an Access form form one record at a time. A form allows you to view your data one record at a time. maintaining viewing printing Forms are useful for maintaining, viewing, and printing records in a database. Forms Design window Forms Wizard You can create your own form in the Forms Design window or you can use the Forms Wizard to create a form. AutoForm Wizard. The easiest way to create a form is to use the AutoForm Wizard.

Use the AutoForm Wizard AutoForm Wizard The AutoForm Wizard uses a table (or query) you select as the basis to create a form that displays all the fields of the table (or query). view the records one record at a time. Once you have created your form, you can view the records one record at a time. navigation bar The form has a navigation bar just like the navigation bar you have already used in the Table or Query Datasheet view.

The Report Preview window When a report has been created, you can preview it on the screen. navigation buttons You can navigate through the pages in the report by using the navigation buttons at the bottom of the preview.

report You can create a report, which is a printed version of your data, that is formatted according to your specifications. data from a single table multiple tables The data in the report can consist of data from a single table or multiple tables. Reports Wizard Access has a Reports Wizard that allows you to easily create a report. based on a table based on a query The report can be based on a table or it can be based on a query. – –If the report is based on a query, it will contain the same fields that were selected for the query Create, preview, and navigate a report

Backup and restore a database backup You may want to create a backup of your data so that if you lose or damage your database, you can recover from the backup. You can use a backup tool, such as the Microsoft backup tool, or some other backup program. To restore use the same backup tool To restore the data from the backup, you need to use the same backup tool according to the instructions associated with that tool.

Compacting reduces database storage size Compacting a database reduces the space used by the database, making the space available for other uses.

Setting the Compact on Close option Select the General tab of the Options dialog box. Click the check box to insert a check mark so the database will be compacted every time it is closed.

Compacting a database compact and repair recover wasted space It is a good idea to periodically compact and repair a database to recover wasted space created by adding, deleting, and modifying records. Access has a Compact and Repair feature: – –Open a database – Tools Options –Click on Tools and then Options – Compact on Close. option will cause your database to be compacted and repaired every time you close it –On the Options menu, select Compact on Close. Selecting this option will cause your database to be compacted and repaired every time you close it

Convert an existing database to Access 2002 format It is possible to convert a database created in Access 2000 to an Access 2002 database. To convert an Access 2000 database to Access 2002 format: – database to be converted is closed –Make certain the database to be converted is closed – Tools Database Utilities –Click Tools on the menu bar, then point to Database Utilities – Convert database format to convert to –Point to Convert database and choose the format to convert to –Enter the name name for the converted database –Enter the name of the database to convert, and a name for the converted database to be stored under

Steps to complete Tutorial 1 described on pages AC1.27 to Seasons.mdb 4. Copy “ Seasons.mdb ” to your classwork folder Table 1Employers Rename “ Table 1 ” as “ Employers ” 5. Employer 5. Open “ Employer ” table 6.set page setup options for printing 6. Open Help – “ set page setup options for printing ” for a table, query, form or report Select “ for a table, query, form or report ” Read explanation & close

Steps to complete Tutorial 1 described on pages AC1.27 to Create Query w/wizard Employers Table = “ Employers ” >City Fields = in this order: >City >Employer Name >Contact First Name >Contact Last Name >Phone fields Next>> Employer Phone List Name = “Employer Phone List ” Modify Query Design… City Sort “City ” ascending

Steps to complete Tutorial 1 described on pages AC1.27 to Autoform 8. Autoform Wizard Employers Create Form using “Employers” table All Fields Columnar format Standard = OK Employer Info Name form “Employer Info” Open form to view or enter info “Open form to view or enter info” What’s this Click on Help “What’s this” & point to Record # box Goto Record #42

Steps to complete Tutorial 1 described on pages AC1.27 to 1.28 Employers Table 12.Auto Report Wizard on “Employers Table” Employers Save as ”Employers” Seasons 13.Set option to compact “Seasons” database on close 14. Convert to: Seasons 2002 Access 2002 format & save as “Seasons 2002” Seasons 97 Access 97 format & save as “Seasons 97” View differences in the file sizes with a file manager 15. Exit 15. Exit Access