MACROMEDIA COLDFUSION 5-DEVELOPING, Develop Manual

Page: 49 / 438

Building Queries 29
Reviewing the code
The query you just created retrieves data from the CompanyInfo database. The
following table describes the code and its function:
Query notes and considerations
When creating queries to retrieve data, keep the following guidelines in mind:
•
Enter the query
name
and
datasource
attributes in the begin
cfquery
tag.
•
Surround attribute settings with double quotes(").
•
Make sure that a data source exists in the ColdFusion Administrator before you
reference it n a
cfquery
tag. Alternatively, use the
dbtype = "dynamic"
and
queryString
attributes to dynamically specify a database.
•
The SQL that you write is sent to the database and performs the actual data
retrieval.
•
Columns and tables that you refer to in your SQL statement must exist, otherwise
the query will fail.
•
Reference the query data by naming the query in one of the presentation tags,
such as
cfoutput
,
cfgrid
,
cftable
,
cfgraph
, or
cftree
later on the page.
Code Description
<cfquery name="EmpList"
datasource="CompanyInfo">
Queries the database specified in the
CompanyInfo data source
SELECT FirstName, LastName,
Salary, Contract
FROM Employee Gets information from the FirstName,
LastName, Salary, and Contract fields in
the Employee table
</cfquery> Ends the
cfquery
block