The Language of SQL- P19 potx

... one set of parentheses, the innermost set of functions always gets evaluated first. The same is true of parentheses used in Boolean expressions. In this example, the innermost set of parentheses ... two sets of parentheses in this statement. Our use of parentheses here is analogous to the parentheses used in the composite functions seen in Chapter 4. With regard to funct...

Ngày tải lên: 05/07/2014, 05:20

... not restricted to the columns that happen to be in the table. The concept of calculated fields allows for a number of other possibilities. With calculated fields, you can do the following: ■ Select ... column. Notice two things. First, the literal ‘First Name’ is repeated on every row. Second, there is no header information for the first column. When run in Microsoft SQL Serve...

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... is listed to the right of the LEFT JOIN keyword. In right joins, the primary table is listed to the right of the RIGHT JOIN keyword. The secondary table is listed to the left of the RIGHT JOIN ... table, even if there are no matches with any rows in the secondary table. In the first specified LEFT JOIN, the Customers table is on the left and the Orders table is...

Ngày tải lên: 05/07/2014, 05:20

... dat e on which the test was taken ■ TotalPoints: The total number of possible poi nts for the test ■ Grade: The number of points that the student received Chapter 19 ■ Principles of Database Design196 So ... list the information that each column in this table is meant to provide. The columns are: ■ Test: A description of the test or quiz given ■ Student: The student...

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... OS is a registered trademark of Apple Inc. PostgreSQL is a trademark of PostgreSQL Inc and the Regents of the University of California. Allothertrademarksarethepropertyoftheirrespectiveowners. Allimages†CengageLearningunlessotherwisenoted. LibraryofCongressControlNumber:2010925128 ISBN-13:978-1-4354-5751-5 ISBN-10:1-4354-5751-X Course ... Lisa The Language of SQL Larry Rocko...

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... The 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 ... area of expertise is with data warehouse systems and reporting tools. He recently developed a suite of BI tools for ASA P Software, a subsidiary of Dell Inc. He holds an MBA from the University of Chi...

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... the introduction of any book they happen to read and then proceed immediately to the first real chapter. With that fact firmly in mind, we will only cover relatively unimportant material in the ... Appendix D, for a description of the files available on the companion Web site. These files list all SQL statements and provide all data shown in the book. You may download the co...

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... that time. Generally speaking, there are three major components of the SQL language. The first is called DML, or Data Manipulation Language. This module of the language allows you to retrieve, ... been The Logic of SQL. This is because, like all computer languages, the language of SQL has much more to do with cold, hard logic than with English vocabulary. Nevertheless,...

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... stored in any number of tables. The term relational is used to indicate that the tables are related to each other. For example, let’s take the simple case of a database consisting of only two tables: ... and the data they contain. The common custom is to display a table as a grid of rows and columns. Each row represents a record in the table. Each column represents a field...

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... statement. The FROM keyword is used to designate the table from which data is to be retrieved. The name of the table follows the FROM. In this case, the table name is Customers. As is the custom, ... such, the principles of database design will be much more meaningful after you’re more aware of the details and nuances of retrieving some data. So we’re going to tempor...

Ngày tải lên: 05/07/2014, 05:20