The Language of SQL- P3 pot

... 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...

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...

Ngày tải lên: 05/07/2014, 05:20

... desired data by the specified columnlist, in descending order. The outer SELECT statement then retrieves data from the inner SELECT using the ROWNUM keyword to limit the number of rows that are ... statement truly useful. With the WHERE clause, you can now issue a statement that retrieves all customers from the state of New York. The related topic of limiting the numbe...

Ngày tải lên: 05/07/2014, 05:20

... 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

... variations of the join, the inner join and the outer join. Outer joins will be covered in the next chapter. The Inner Join 113 An alternate way of specifying the same inner join without the INNER ... advantage of the INNER JOIN and ON keywords is that they explicitly present the logic of the join. That is their only purpose. Although it is possible to specify the...

Ngày tải lên: 05/07/2014, 05:20

... 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...

Ngày tải lên: 05/07/2014, 05:20

... automatically, to display a total of 240. There are, of course, numerous other features and capabilities of this and other reporting tools. The main point is to remain mindful of what can accomplished with ... users. Examples of this type of software include Microsoft Reporting Services and Crystal Reports. These software packages allow developers to connect to database s via SQ...

Ngày tải lên: 05/07/2014, 05:20

... Express. Click the INSTALL button. 6. On the License screen, click the I ACCEPT button. The software will then be installed. During the installation, you may see a window warning of compati bility ... do this, find the Object Explorer pane on the left side of the window. Right-click on the DATABASES line and then select NEW DATABASE. In the New Database win- dow, enter...

Ngày tải lên: 05/07/2014, 05:20

... middle of values, 33 updating, 180 181 database design art of, 202 203 normalization, 196 199 Data Control Language (DCL), explained, 3 Data Definition Language (DDL). See DDL (Data Definition Language) data, ... 99 omission of space and left parenthesis, 98 99 as open source database, 4 reference manual, 223 stored procedures, 165, 167 treatment of literal values, 21 use of ac...

Ngày tải lên: 05/07/2014, 05:20