11 Chapter 2 Basic Data Retrieval.. 27 Chapter 4 Using Functions.. 44 Chapter 5 Sorting Data.. 107 Chapter 11 Combining Tables with an Inner Join.. 112 Table Order in Inner Joins.. 116 C
Trang 1Larry Rockoff has been involved with SQL and Business Intelligence (BI)
de-velopment for many years His main area of expertise is with data warehouse systems and reporting tools He recently developed a suite of BI tools for ASAP Software, a subsidiary of Dell Inc He holds an MBA from the University of Chicago, with a specialization in Management Science.
For more information on his current activities or to contact the author, please visit LarryRockoff.com.
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Trang 2Introduction xii
Chapter 1 Relational Databases and SQL 1
Language and Logic 1
SQL Defined 3
Microsoft SQL Server, Oracle, and MySQL 3
Other Databases 5
Relational Databases 6
Primary and Foreign Keys 7
Datatypes 8
NULL Values 10
The Significance of SQL 10
Looking Ahead 11
Chapter 2 Basic Data Retrieval 13
A Simple SELECT 13
Syntax Notes 15
Specifying Columns 16
Column Names with Embedded Spaces 17
Looking Ahead 18
Chapter 3 Calculations and Aliases 19
Calculated Fields 19
Literal Values 20 vi
Trang 3Arithmetic Calculations 22
Concatenating Fields 23
Column Aliases 24
Table Aliases 26
Looking Ahead 27
Chapter 4 Using Functions 29
The Function of Functions 29
Character Functions 30
Composite Functions 36
Date/Time Functions 37
Numeric Functions 40
Conversion Functions 41
Looking Ahead 44
Chapter 5 Sorting Data 47
Adding a Sort 47
Sorting in Ascending Order 48
Sorting in Descending Order 49
Sorting by Multiple Columns 50
Sorting by a Calculated Field 51
More on Sort Sequences 52
Looking Ahead 55
Chapter 6 Column-Based Logic 57
IF-THEN-ELSE Logic 57
The Simple Format 58
The Searched Format 60
Looking Ahead 62
Chapter 7 Row-Based Logic 63
Applying Selection Criteria 63
WHERE Clause Operators 65
Limiting Rows 66
Limiting Rows with a Sort 68
Looking Ahead 70
Chapter 8 Boolean Logic 71
Complex Logical Conditions 71
Trang 4The AND Operator 72
The OR Operator 73
Using Parentheses 73
Multiple Sets of Parentheses 75
The NOT Operator 76
The BETWEEN Operator 79
The IN Operator 80
Boolean Logic and NULL Values 82
Looking Ahead 84
Chapter 9 Inexact Matches 85
Pattern Matching 85
Wildcards 88
Matching by Sound 91
Looking Ahead 93
Chapter 10 Summarizing Data 95
Eliminating Duplicates 95
Aggregate Functions 97
The COUNT Function 99
Grouping Data 101
Multiple Columns and Sorting 103
Selection Criteria on Aggregates 105
Looking Ahead 107
Chapter 11 Combining Tables with an Inner Join 109
Joining Two Tables 110
The Inner Join 112
Table Order in Inner Joins 114
Alternate Specification of Inner Joins 114
Table Aliases Revisited 115
Looking Ahead 116
Chapter 12 Combining Tables with an Outer Join 119
The Outer Join 119
Left Joins 122
Testing for NULL Values 124
Right Joins 125
Table Order in Outer Joins 125
Contents
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Trang 5Full Joins 126
Looking Ahead 128
Chapter 13 Self Joins and Views 131
Self Joins 131
Creating Views 134
Referencing Views 136
Benefits of Views 137
Modifying and Deleting Views 138
Looking Ahead 139
Chapter 14 Subqueries 141
Types of Subqueries 141
Using a Subquery as a Data Source 142
Using a Subquery in Selection Criteria 145
Correlated Subqueries 147
The EXISTS Operator 149
Using a Subquery as a Calculated Column 150
Looking Ahead 151
Chapter 15 Set Logic 153
Using the UNION Operator 154
Distinct and Non-Distinct Unions 157
Intersecting Queries 158
Looking Ahead 160
Chapter 16 Stored Procedures and Parameters 163
Creating Stored Procedures 164
Parameters in Stored Procedures 166
Executing Stored Procedures 168
Modifying and Deleting Stored Procedures 169
Functions Revisited 170
Looking Ahead 171
Chapter 17 Modifying Data 173
Modification Strategies 173
Inserting Data 174
Deleting Data 178
Updating Data 180