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Microsoft Access 2002. Tutorial 5 – Enhancing a Table’s Design, and Creating Advanced Queries and Custom Forms. New Data Files!. Don’t work on the file you created so far Go to ’Tutorial.05’ folder. Preventing Input Errors. Different techniques Lookup Wizard Pick value from list
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Microsoft Access 2002 Tutorial 5 – Enhancing a Table’s Design, and Creating Advanced Queries and Custom Forms
New Data Files! • Don’t work on the file you created so far • Go to ’Tutorial.05’ folder
Preventing Input Errors • Different techniques • Lookup Wizard • Pick value from list • Input Mask • Input is always on correct form, can’t enter letters in number field etc. • Validation Criteria • Anything can be entered, but only specific values are accepted by Access
A Lookup Wizard field in a table • To make a form easier to use, you will often add a Lookup Wizard to the form. • Instead of remembering a particular value, you can pick the value from a list. • This approach insures that you cannot enter an invalid value. • When you create the Lookup Wizard, you will provide a list of acceptable values from which other users will make a selection.
A lookup field in Datasheet view When the user selects a description, Access will return the correct code that corresponds to the description. This figure below shows what the Lookup field looks like in the table datasheet. In this example, the NAICS description is displayed. When you select a description, Access will lookup the code that goes with the descriptions.
Input mask for a table field • Some fields require special characters to make them more readable. • Example: phone number, (920) 424-0166 • Create an input mask that will display these characters as a predefined format. • This predefined format can be used to enter or display data in a field. • If literal display characters are defined, the user will not need to enter those characters. • Use the Input Mask Wizard
Input Mask character descriptions This figure shows the input mask characters that are available and the meaning of each character. More characters/options available. Press F1 to see all.
Data Validation Demonstrate in Jobs database
Pattern Match Query • You may want to view only records that match a particular criteria. You can do this by creating a query that uses a pattern match. • Wildcard characters • *: Match with any number of characters • ?: Match a single character • #: Match a single digit • Use with like operator • Like ”508*” • Like ”#ab?cd*” (give an example of a string that matches) • Can also use with in operator • In (”ME”, ”NH”, ”WI”) • In (”Ma*”, ”DE?”) • Not In (”ME”, ”MA”)
A design grid with a pattern match field This figure illustrates a criteria that specifies that only records whose phone numbers begin with 508 will be included in the datasheet. Notice that the * following the ‘8’ creates a wildcard, meaning that anything that follows the 508 is acceptable.
A list of values expand the selection possibilities This design grid shows a field with a list of values. As long as the State value in any record is one of those in the list, the record will be included in the datasheet.
Use both the And and Or logical operators in the same query • There will be circumstances where you will want to use both the And and Or logical operators in the same query. • The In operator naturally creates an Or condition. You can also use the key word Or in the criteria row to create an Or condition. • Placing two conditions on the same row of the Criteria in the Query design grid creates an And condition. • Placing two conditions on separate rows in the Query design grid creates an Or condition.
And and Or conditions in the same query Placing conditions in the same criteria row creates an AND condition. In this example, both criteria also create OR conditions, resulting in a match condition using AND and OR.
Result for the combined use of And and Or The criteria for the State field specified that the State must be either MA or NH. The second criteria, for the Position Title field, specified that the values must be Waiter/Waitress or Kitchen Help. The criteria, in this case, uses the Or operator. This criteria could have also been created by placing the two positions on separate lines in the query design grid.
Create a parameter query • Sometimes when you create a query, you don't know exactly which records the user might want to see. • To allow flexibility in the query, you can create a parameter query. • The parameter query will prompt the user to enter the value they want to use to select records. • Once the user has supplied this information, those records that match the value will be displayed in the query datasheet.
Defining a parameter query Note that the parameter query is enclosed in brackets. This text will be the user prompt when the query is run. The figure below shows a parameter query placed in the criteria row. When the parameter query is run, a dialog box will be displayed asking the user to enter a value that they want to specify for the criteria.