XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 1 Analyzing Data For Effective Decision Making Chapter 3 “The human problems which I deal with every day—concerning employees as well as customers—are the problems that fascinate me, that seem important to me.” —Hortense Odlum

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 2 Level 2 Objectives: Creating More Complex Queries Design queries that compare data from more than one table Refine table relationships by specifying the join type Perform calculations in queries Customize queries and their results

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 3 Evaluating Data Using Special Types of Queries

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 4 Using Queries to Find Duplicate Records Duplicates Query Wizard  Searches for duplicate values in fields  Improve business operations  Designed to identify records that contain same information in particular field

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 5 Using Queries to Find Unmatched Records Find Unmatched Query Wizard  Compares records in two specified tables or recordsets  Finds all records in one table or query that have no related records in second table or query  Requires that two tables being compared have common field

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 6 Limiting the Records in the Query Results Limiting results to only a few records often aids analysis Top Values query  Sorts and then filters records  Display specified number of records that contain top or bottom values  Top Values list box on query design toolbar

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 7 Top Values Query Design and Results

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 8 Using Parameter Values in Queries Parameter values  Phrase usually in form of a question or instruction  Enclosed in square brackets  Serves as prompt to user to enter value  Example [Enter a job ID]

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 9 Parameter Query to Allow User Input when the Query Is Run

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 10 Analyzing Data from More than One Table Data from more than one table required to answer question  Combine records from two or more tables  Display only information needed Work in design view to specify criteria for selecting records from multiple tables Lines between tables link primary key to foreign key field  Primary key designated with 1  Foreign key designated with ∞

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 11 Analyzing Data from More than One Table (continued) Join tables  Linking of tables using primary and foreign keys  Established relationship  Or Each table shares field with same or compatible data type One join field primary key If tables do not include fields that can be joined  Add one or more extra tables or queries  Link tables that contain the data

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 12 Analyzing Data from More than One Table (continued) Use queries as source of underlying data for another query in place of one or more tables Create queries based on more than one object  Should not use any table or query that does not have common field with at least one of the other tables or queries  Otherwise Access displays every combination of records between two tables

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 13 Refining Relationships with Appropriate Join Types Inner join  Displays all records in one table that have corresponding values in common field in another table  Records must match before being displayed in query results Outer join  Display all records of one table  Regardless of whether corresponding record stored in related table

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 14 Inner Join

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 15 Left Outer Join

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 16 Right Outer Join

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 17 Refining Relationships with Appropriate Join Types (continued) Outer join types  Left  Right Use join properties dialog box  To change join type  By default tables related using inner joins

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 18 Using Logical Operators to Specify Multiple Conditions Logical operators  Test values that can only be true or false Place conditions in separate fields in same criteria row of design grid  All conditions in row must be met to select record NOT logical operator  Excludes values that don’t meet criterion

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 19 Logical Operators

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 20 Performing Calculations with Queries Any information derived from fields in table or query should be calculated in query  Rather than included as data in table Calculation types  Predefined Compute amounts for groups of records or for all records combined in query  Custom Performs numeric date and text computations on each record Using data from one or more fields

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 21 Calculating Statistical Information Aggregate functions  Arithmetic and statistical operations  Apply to records that meet query’s selection criteria

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 22 Aggregate Functions

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 23 Using Aggregate Functions in a Query

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 24 Creating Calculated Fields in a Query Expression  Arithmetic formula used to make calculation  Use standard arithmetic operators  Use parenthesis for complex expressions Calculated field  Add to query design grid  Type expression Expression builder  Build complex expressions

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 25 Creating Calculated Fields in a Query (continued) Function  Perform standard calculation  Return value Date()  Provides today’s date Field properties  Change format and number of decimal places for calculated field

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 26 Field Properties

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 27 Concatenating in Queries Concatenation  Combining contents of two or more fields  Operator &  Example Name [EmpFirst]& " " & [EmpLast]

XP Chapter 3 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 28 Level 2 Summary Use queries to select data from more than one table Join types  Inner  Right outer  Left outer Calculated field types  Predefined  Custom