- •Preface
- •Introduction
- •Lesson Objectives
- •Lesson Agenda
- •Course Objectives
- •Course Agenda
- •Appendixes Used in the Course
- •Lesson Agenda
- •Oracle Database 11g: Focus Areas
- •Oracle Database 11g
- •Oracle Fusion Middleware
- •Oracle Enterprise Manager Grid Control 10g
- •Oracle BI Publisher
- •Lesson Agenda
- •Relational and Object Relational Database Management Systems
- •Data Storage on Different Media
- •Relational Database Concept
- •Definition of a Relational Database
- •Data Models
- •Entity Relationship Model
- •Relating Multiple Tables
- •Relational Database Terminology
- •Lesson Agenda
- •Using SQL to Query Your Database
- •SQL Statements
- •Development Environments for SQL
- •Lesson Agenda
- •The Human Resources (HR) Schema
- •Tables Used in the Course
- •Lesson Agenda
- •Oracle Database 11g Documentation
- •Additional Resources
- •Summary
- •Practice I: Overview
- •Objectives
- •Lesson Agenda
- •Capabilities of SQL SELECT Statements
- •Basic SELECT Statement
- •Selecting All Columns
- •Selecting Specific Columns
- •Writing SQL Statements
- •Column Heading Defaults
- •Lesson Agenda
- •Arithmetic Expressions
- •Using Arithmetic Operators
- •Operator Precedence
- •Defining a Null Value
- •Null Values in Arithmetic Expressions
- •Lesson Agenda
- •Defining a Column Alias
- •Using Column Aliases
- •Lesson Agenda
- •Concatenation Operator
- •Literal Character Strings
- •Using Literal Character Strings
- •Alternative Quote (q) Operator
- •Duplicate Rows
- •Lesson Agenda
- •Displaying the Table Structure
- •Using the DESCRIBE Command
- •Quiz
- •Summary
- •Practice 1: Overview
- •Objectives
- •Lesson Agenda
- •Limiting Rows Using a Selection
- •Limiting the Rows That Are Selected
- •Using the WHERE Clause
- •Character Strings and Dates
- •Comparison Operators
- •Using Comparison Operators
- •Range Conditions Using the BETWEEN Operator
- •Membership Condition Using the IN Operator
- •Pattern Matching Using the LIKE Operator
- •Combining Wildcard Characters
- •Using the NULL Conditions
- •Defining Conditions Using the Logical Operators
- •Using the AND Operator
- •Using the OR Operator
- •Using the NOT Operator
- •Lesson Agenda
- •Rules of Precedence
- •Lesson Agenda
- •Using the ORDER BY Clause
- •Sorting
- •Lesson Agenda
- •Substitution Variables
- •Using the Single-Ampersand Substitution Variable
- •Character and Date Values with Substitution Variables
- •Specifying Column Names, Expressions, and Text
- •Using the Double-Ampersand Substitution Variable
- •Lesson Agenda
- •Using the DEFINE Command
- •Using the VERIFY Command
- •Quiz
- •Summary
- •Practice 2: Overview
- •Objectives
- •Lesson Agenda
- •SQL Functions
- •Two Types of SQL Functions
- •Single-Row Functions
- •Lesson Agenda
- •Character Functions
- •Case-Conversion Functions
- •Using Case-Conversion Functions
- •Character-Manipulation Functions
- •Using the Character-Manipulation Functions
- •Lesson Agenda
- •Number Functions
- •Using the ROUND Function
- •Using the TRUNC Function
- •Using the MOD Function
- •Lesson Agenda
- •Working with Dates
- •RR Date Format
- •Using the SYSDATE Function
- •Arithmetic with Dates
- •Using Arithmetic Operators with Dates
- •Lesson Agenda
- •Date-Manipulation Functions
- •Using Date Functions
- •Using ROUND and TRUNC Functions with Dates
- •Quiz
- •Summary
- •Practice 3: Overview
- •Objectives
- •Lesson Agenda
- •Conversion Functions
- •Implicit Data Type Conversion
- •Explicit Data Type Conversion
- •Lesson Agenda
- •Using the TO_CHAR Function with Dates
- •Elements of the Date Format Model
- •Using the TO_CHAR Function with Dates
- •Using the TO_CHAR Function with Numbers
- •Using the TO_NUMBER and TO_DATE Functions
- •Using the TO_CHAR and TO_DATE Function with RR Date Format
- •Lesson Agenda
- •Nesting Functions
- •Lesson Agenda
- •General Functions
- •NVL Function
- •Using the NVL Function
- •Using the NVL2 Function
- •Using the NULLIF Function
- •Using the COALESCE Function
- •Lesson Agenda
- •Conditional Expressions
- •CASE Expression
- •Using the CASE Expression
- •DECODE Function
- •Using the DECODE Function
- •Quiz
- •Summary
- •Practice 4: Overview
- •Objectives
- •Lesson Agenda
- •What Are Group Functions?
- •Types of Group Functions
- •Group Functions: Syntax
- •Using the AVG and SUM Functions
- •Using the MIN and MAX Functions
- •Using the COUNT Function
- •Using the DISTINCT Keyword
- •Group Functions and Null Values
- •Lesson Agenda
- •Creating Groups of Data
- •Creating Groups of Data: GROUP BY Clause Syntax
- •Using the GROUP BY Clause
- •Grouping by More than One Column
- •Using the GROUP BY Clause on Multiple Columns
- •Illegal Queries Using Group Functions
- •Restricting Group Results
- •Restricting Group Results with the HAVING Clause
- •Using the HAVING Clause
- •Lesson Agenda
- •Nesting Group Functions
- •Quiz
- •Summary
- •Practice 5: Overview
- •Objectives
- •Lesson Agenda
- •Types of Joins
- •Joining Tables Using SQL:1999 Syntax
- •Qualifying Ambiguous Column Names
- •Lesson Agenda
- •Creating Natural Joins
- •Retrieving Records with Natural Joins
- •Creating Joins with the USING Clause
- •Joining Column Names
- •Retrieving Records with the USING Clause
- •Using Table Aliases with the USING Clause
- •Creating Joins with the ON Clause
- •Retrieving Records with the ON Clause
- •Creating Three-Way Joins with the ON Clause
- •Applying Additional Conditions to a Join
- •Lesson Agenda
- •Joining a Table to Itself
- •Self-Joins Using the ON Clause
- •Lesson Agenda
- •Nonequijoins
- •Retrieving Records with Nonequijoins
- •Lesson Agenda
- •INNER Versus OUTER Joins
- •LEFT OUTER JOIN
- •RIGHT OUTER JOIN
- •FULL OUTER JOIN
- •Lesson Agenda
- •Cartesian Products
- •Generating a Cartesian Product
- •Creating Cross Joins
- •Quiz
- •Summary
- •Practice 6: Overview
- •Objectives
- •Lesson Agenda
- •Using a Subquery to Solve a Problem
- •Subquery Syntax
- •Using a Subquery
- •Guidelines for Using Subqueries
- •Types of Subqueries
- •Lesson Agenda
- •Single-Row Subqueries
- •Executing Single-Row Subqueries
- •Using Group Functions in a Subquery
- •The HAVING Clause with Subqueries
- •What Is Wrong with This Statement?
- •No Rows Returned by the Inner Query
- •Lesson Agenda
- •Multiple-Row Subqueries
- •Lesson Agenda
- •Null Values in a Subquery
- •Quiz
- •Summary
- •Practice 7: Overview
- •Objectives
- •Lesson Agenda
- •Set Operators
- •Set Operator Guidelines
- •The Oracle Server and Set Operators
- •Lesson Agenda
- •Tables Used in This Lesson
- •Lesson Agenda
- •UNION Operator
- •Using the UNION Operator
- •UNION ALL Operator
- •Using the UNION ALL Operator
- •Lesson Agenda
- •INTERSECT Operator
- •Using the INTERSECT Operator
- •Lesson Agenda
- •MINUS Operator
- •Using the MINUS Operator
- •Lesson Agenda
- •Matching the SELECT Statements
- •Matching the SELECT Statement: Example
- •Lesson Agenda
- •Using the ORDER BY Clause in Set Operations
- •Quiz
- •Summary
- •Practice 8: Overview
Restricting Group Results
with the HAVING Clause
When you use the HAVING clause, the Oracle server restricts groups as follows:
1.Rows are grouped.
2.The group function is applied.
3.Groups matching the HAVING clause are displayed.
|
|
SELECT |
column, group_function |
|
|
|
|
|
FROM |
table |
|
|
|
|
|
[WHERE |
condition] |
|
|
|
|
|
[GROUP BY |
group_by_expression] |
|
|
|
|
|
[HAVING |
group_condition] |
|
|
|
|
|
[ORDER BY column]; |
|
|
|
|
|
|
|
Copyright © 2009, Oracle. All rights reserved. |
|
|
|
Restricting Group Results with the HAVING Clause |
Academy |
|||||
|
|
|
|
|
||
You use the HAVING clause to specify the groups that are to be displayed, thus further restricting the groups on the basis of aggregate information.
In the syntax, group_condition restricts the groups of rows returned to those groups for which
Oracle
The Oracle server performs the following steps when you use the HAVING clause: |
|||
1. |
Rows are grouped. |
& |
Only |
|
|||
2. |
The group function is applied to the group. |
||
3. |
The groups that match the c iteria in the HAVING clause are displayed. |
||
The HAVING clauseInternalcan pr c de the GROUseP BY clause, but it is recommended that you place the GROUP BY clause first because it is more logical. Groups are formed and group functions are
calculated before the HAVING clause is applied to the groups in the SELECT list. Oracle
Oracle Database 11g: SQL Fundamentals I 5 - 22
Using the HAVING Clause
SELECT department_id, MAX(salary)
FROM employees
GROUP BY department_id
HAVING MAX(salary)>10000 ;
Copyright © 2009, Oracle. All rights reserved.
Using the HAVING Clause |
Academy |
|
|
The example in the slide displays the department numbers and maximum salaries for those |
|
departments with a maximum salary greater than $10,000. |
|
You can use the GROUP BY clause without using a group function in the SELECT list. If you restrict |
||||
rows based on the result of a group function, you must have a GROUP BY clause as well as the |
||||
HAVING clause. |
|
|
Oracle |
|
|
|
& |
|
|
|
|
|
|
|
The following example displays the department numbers a d average salaries for those departments |
||||
with a maximum salary greater than $10,000: |
Only |
|||
SELECT |
depa tme t id, AVG(salary) |
|||
FROM |
|
employees |
|
|
GROUP BY department id |
|
|||
|
|
|
Use |
|
HAVING |
max(salary)>10000; |
|
||
|
Internal |
|
||
Oracle |
|
|
|
|
Oracle Database 11g: SQL Fundamentals I 5 - 23
Using the HAVING Clause
|
SELECT |
job_id, SUM(salary) PAYROLL |
|
|
FROM |
employees |
|
|
WHERE |
job_id NOT LIKE '%REP%' |
|
|
GROUP BY |
job_id |
|
|
HAVING |
SUM(salary) > 13000 |
|
|
ORDER BY |
SUM(salary); |
|
|
|
|
|
|
Copyright © 2009, Oracle. All rights reserved. |
Academy |
|
|
|
||
Using the HAVING Clause (continued) |
Oracle |
||
|
|
||
The example in the slide displays the job ID and total monthly sa ary for each job that has a total payroll exceeding $13,000. The example excludes sales representatives and sorts the list by the total monthly salary.
& |
Only |
Internal |
|
Use |
|
Oracle |
|
Oracle Database 11g: SQL Fundamentals I 5 - 24
Lesson Agenda
•Group functions:
–Types and syntax
–Use AVG, SUM, MIN, MAX, COUNT
–Use DISTINCT keyword within group functions
–NULL values in a group function
•Grouping rows:
–GROUP BY clause
–HAVING clause
•Nesting group functions
|
Copyright © 2009, Oracle. All rights reserved. |
Academy |
||
|
|
|||
|
|
Oracle |
||
& |
Only |
|
||
|
Internal |
|
|
|
|
Use |
|
||
Oracle |
|
|
|
|
Oracle Database 11g: SQL Fundamentals I 5 - 25