1. Objectives Query for top values Create a parameter query
Modify query properties
Create an update query
Creating Advanced Queries Unit K

2. Objectives Create a make-table query Create an append query
Create a delete query
Creating Advanced Queries Unit K

3. Introduction
Queries are database objects that answer questions about the data.
A select query creates a single datasheet to display the fields and records that match specific criteria
An action query is one that makes changes to the data
Types of action queries: delete, update, append, and make-table
Creating Advanced Queries Unit K

4. Querying for Top Values
Use the Top Values feature in Query Design View to specify a number or percentage of records that you want to display.
Select a subset of the highest or lowest values in a sorted query
Creating Advanced Queries Unit K

5. Querying for Top Values (cont.)
Top Values list arrow
Totals button
Count LogNo
Group By Description
Creating Advanced Queries Unit K

6. Querying for Top Values (cont.)
Top Value options
Creating Advanced Queries Unit K

7. Creating a Parameter Query
A parameter query displays a dialog box that prompts you for an entry.
The entry is used as criteria for the query
The entry narrows the number of records that appear in the datasheet
Can build a form or report based on a parameter query
Creating Advanced Queries Unit K

8. Creating a Parameter Query (cont.)
Parameter prompt
Parameter criteria
Creating Advanced Queries Unit K

9. Creating a Parameter Query (cont.)
Concatenating a parameter prompt to a wildcard character.
You can concatenate (or combine) parameter prompts with a wildcard character such as an asterisk (*) to create more flexible queries
The ampersand (&) is used to concatenate items in an expression
Quotation marks (“”) are used to surround text criteria
Creating Advanced Queries Unit K

10. Modifying Query Properties
Properties are characteristics that define the appearance and behavior of database objects, fields, and controls.
View the properties for an item b opening its property sheet
Creating Advanced Queries Unit K

11. Modifying Query Properties (cont.)
Click here to select the query
Properties button
Query properties
Creating Advanced Queries Unit K

12. Creating an Update Query
An action query changes many records in one process.
In order for an action query to complete its action, you must run the query using the Run button
An update query is a type of action query that updates the values in a field
Creating Advanced Queries Unit K

13. Creating an Update Query (cont.)
Update Query button
Run button
Update To: row
Criteria
Creating Advanced Queries Unit K

14. Creating an Update Query (cont.)
Action queries
Creating Advanced Queries Unit K

15. Creating a Make-Table Query
A make-table query creates a new table of data based on the recordset defined by the query.
Creates a copy of the selected data and pastes it into a new table
The location of the new table can be the current or any other Access database
Creating Advanced Queries Unit K

16. Creating a Make-Table Query (cont.)
Asterisk in the field list
Asterisk in the query grid
Date criteria
Creating Advanced Queries Unit K

17. Creating a Make-Table Query (cont.)
1900 versus 2000 dates.
If you type only two digits of a date, Access assumes that the digits 00 through 29 are for the years 2000 through 2029
If you type 30 through 99, Access assumes the years refer to 1930 through 1999
To specify years outside these ranges, type all four digits
Creating Advanced Queries Unit K

18. Creating an Append Query
An append query adds a selected recordset by a query to an existing table called the target table
Records are copied from one location and a duplicate set is pasted to another location
If the target table has more fields than those you want to append, the append query will ignore the unmatched fields
Creating Advanced Queries Unit K

19. Creating an Append Query (cont.)
Append Query button
Append To: row
Date criteria for Attended field
Creating Advanced Queries Unit K

20. Creating a Delete Query
A delete query deletes a group of records from one or more tables as defined by a query.
Delete queries delete entire records, not just selected fields within records
Creating Advanced Queries Unit K

21. Creating a Delete Query (cont.)
Delete Query button
Delete: row
Creating Advanced Queries Unit K

22. Creating a Delete Query (cont.)
Reviewing referential integrity.
Referential integrity between two tables is established when tables are joined
It ensures that no orphaned records currently exist or are added to the database
Related tables have an orphan record when information in the foreign key field of the “many” table doesn't have a matching entry in the primary key field of the “one” table
Creating Advanced Queries Unit K

23. Creating a Delete Query (cont.)
Reviewing referential integrity (cont.).
An orphan record is sometimes called an unmatched record
The term “orphan” corresponds to the “one” table as containing parent records, and the “many” table as containing child records
A child record cannot be created without a corresponding parent record
Creating Advanced Queries Unit K

24. Specifying Join Properties
When more than one table’s field list is used in a query, the tables are joined as defined in the relationships window.
If referential integrity is enforced, a “1” appears next to the field that serves as the “one” side of the one-to-many relationship
Usually the primary key field for its table
Creating Advanced Queries Unit K

25. Specifying Join Properties (cont.)
If referential integrity is enforced, an infinity sign appears next to the field that serves as the “many” side of the one-to-many relationship
The foreign key field for its table
Edit table relationships for an individual query in Query Design View by double-clicking the join line
Creating Advanced Queries Unit K

26. Specifying Join Properties (cont.)
Double-click the join line to open the Join Properties dialog box
Default join property
Creating Advanced Queries Unit K

27. Specifying Join Properties (cont.)
The Join line’s appearance shows that all records in the Courses table will be included in the datasheet
Creating Advanced Queries Unit K

28. Specifying Join Properties (cont.)
Finding duplicate and unmatched records.
Use the Find Duplicates Query Wizard and Find Unmatched Query Wizard to help find duplicate and unmatched records
Creating Advanced Queries Unit K