Database Reference
In-Depth Information
Example 6: Example 33 from Chapter 12 is repeated here to illustrate the point:
We desire a list from the employee table (of the Oracle default database), showing for
each department, the total salary, average salary, minimum salary, maximum salary
and standard deviation; we want to show only departments with a total salary of at least
$600,000:
Example 7: Referring to the default Oracle database, suppose we want to list
employees beyond a certain hire year. Following is an incorrect SQL statement followed
by a correct SQL statement for the problem:
15.6 If-Then Limitation
In Chapter 8 (section 8.2), it was mentioned that one form of a WFF is as follows:
It appears that this format is seldom implemented in typical SQL implementations
(though there are deviations of it). The work-around is to apply the appropriate
standardization rule (review section 8.4 of Chapter 8), which is shown below:
This is by no means a significant setback. One can get by without ever using
an if-then construct, and simply using its equivalent.
 
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