Transcript Chapter 7

Chapter 7
Query-by-Example
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© Pearson Education Limited 1995, 2005
Chapter 7 - Objectives
 The
main features of Query-By-Example (QBE).
 The
types of queries provided by the Microsoft
Access DBMS QBE facility.
 How
to use QBE to build queries to select fields
and records.
 How
to use QBE to target single or multiple tables.
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© Pearson Education Limited 1995, 2005
Chapter 7 - Objectives
 How
to perform calculations using QBE.
 How
to use advanced QBE facilities including
parameter, find matched, find unmatched,
crosstab, and autolookup queries.
 How
to use QBE action queries to change
content of tables.
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Query-by-Example (QBE)

Visual approach for accessing information in a
database through use of query templates.

Example values are entered into template to
represent what access to database is to achieve,
such as the answer to a query.

Originally developed by IBM in 1970s and has
proved so popular that QBE (or similar) is now
provided by most DBMSs.

When user constructs a QBE - in background,
DBMS creates an equivalent SQL statement.
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Query-by-Example (QBE)

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.
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Introduction to Microsoft Access
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Summary of Microsoft Access Query Types
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Introduction to Microsoft Access Queries
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Building Select Queries using QBE Specifying Criteria
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Building Select Queries using QBE Specifying Criteria
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Building Select Queries using QBE Specifying Criteria
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Creating Multi-table Queries
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Calculating Totals
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Calculating Totals
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Using Advanced Queries - Parameter Query
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Using Advanced Queries - Crosstab Query
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Using Advanced Queries - Crosstab Query
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Using Advanced Queries - Find Matched Query
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Using Advanced Queries - Find Unmatched Query
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Using Advanced Queries - Autolookup Query
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Changing Content of Tables - Make-Table
Action Query
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Changing Content of Tables - Delete Action
Query
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Changing Content of Tables - Update
Action Query
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Changing Content of Tables - Append
Action Query
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Changing Content of Tables - Append
Action Query
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