Chapter 9 Query-by-Example Pearson Education © 2009

2 Chapter 9 - Objectives u The main features of Query-By-Example (QBE). u The types of queries provided by the Microsoft Access DBMS QBE facility. u How to use QBE to build queries to select fields and records. u How to use QBE to target single or multiple tables. Pearson Education © 2009

3 Chapter 9 - Objectives u How to perform calculations using QBE. u How to use advanced QBE facilities including parameter, find matched, find unmatched, crosstab, and autolookup queries. u How to use QBE action queries to change content of tables. Pearson Education © 2009

4 Query-by-Example (QBE) u Visual approach for accessing information in a database through use of query templates. u Example values are entered into template to represent what access to database is to achieve, such as the answer to a query. u Originally developed by IBM in 1970s and has proved so popular that QBE (or similar) is now provided by most DBMSs. u When user constructs a QBE - in background, DBMS creates an equivalent SQL statement. Pearson Education © 2009

5 Query-by-Example (QBE) u Allows user to: - Ask questions about data in one or more tables. - Specify the fields we want in the answer. - Select records according to some criteria. - Perform calculations on the data in tables. - Insert and delete records. - Modify values of fields. - Create new fields and tables. Pearson Education © 2009

6 Introduction to Microsoft Access Pearson Education © 2009

7 Summary of Microsoft Access Query Types Pearson Education © 2009

8 Introduction to Microsoft Access Queries Pearson Education © 2009

9 Building Select Queries using QBE - Specifying Criteria Pearson Education © 2009

10 Building Select Queries using QBE - Specifying Criteria Pearson Education © 2009

11 Building Select Queries using QBE - Specifying Criteria Pearson Education © 2009

12 Creating Multi-table Queries Pearson Education © 2009

13 Calculating Totals Pearson Education © 2009

14 Calculating Totals Pearson Education © 2009

15 Using Advanced Queries - Parameter Query Pearson Education © 2009

16 Using Advanced Queries - Crosstab Query Pearson Education © 2009

17 Using Advanced Queries - Crosstab Query Pearson Education © 2009

18 Using Advanced Queries - Find Matched Query Pearson Education © 2009

19 Using Advanced Queries - Find Unmatched Query Pearson Education © 2009

20 Using Advanced Queries - Autolookup Query Pearson Education © 2009

21 Changing Content of Tables - Make-Table Action Query Pearson Education © 2009

22 Changing Content of Tables - Delete Action Query Pearson Education © 2009

23 Changing Content of Tables - Update Action Query Pearson Education © 2009

24 Changing Content of Tables - Append Action Query Pearson Education © 2009

25 Changing Content of Tables - Append Action Query Pearson Education © 2009