Programming instructions

76 Lesson 2 Writing Your First ColdFusion Application
Reviewing the code
The following table describes the code used to build the tripLocation WHERE
subclause:
Note that the preceding code only builds the tripLocation subclause. In the following
exercise you will add code for the other two queryable columns, departureDate and price.
Completing the Trip Search Results page
In the following exercises you will test and modify tripsearchresults.cfm. In the first
exercise, you will test the Trip Search Results page by entering criteria on the Trip Search
form and inspecting the results. In the second exercise, you will finish the code to
construct the complete WHERE clause for all three queryable columns from the Trip
Search form.
Exercise: testing the Trip Search Results page
Follow these steps to test the Trip Search Results page:
1 Copy the tripsearch.cfm and tripsearchresult.cfm files from the solutions directory to
the my_app directory.
2 View the tripsearch.cfm from the my_app directory in your browser and do the
following:
a In the Trip Location drop-down list box select the Begins With option, and enter
the value C in the text box.
b Click Search.
Code Explanation
<cfset WhereClause = " 0=0 ">
The cfset tag initializes the WhereClause
variable to hold the WHERE clause to be
constructed. The initial value is set to "0=0",
so that the WHERE clause has at least one
subclause in case the user enters no search
criteria.
<cfif Form.tripLocationValue GT "">
The cfif tag tests to see if user entered
anything in the Value input box for
tripLocation criterion.
SELECT tripName, tripLocation,
departureDate, returnDate, price, tripID
FROM trips
WHERE #PreserveSingleQuotes(WhereClause)#
SQL query to execute.
PreserveSingleQuotes ColdFusion
function ensures that quotation marks will
passed to the database server as intended.