User Guide
Table Of Contents
- Contents
- The CFML Programming Language
- Elements of CFML
- Using ColdFusion Variables
- Using Expressions and Number Signs
- Using Arrays and Structures
- Contents
- About arrays
- Basic array techniques
- Populating arrays with data
- Array functions
- About structures
- Creating and using structures
- Structure examples
- Structure functions
- Extending ColdFusion Pages with CFML Scripting
- Using Regular Expressions in Functions
- Building Blocks of ColdFusion Applications
- Creating ColdFusion Elements
- Writing and Calling User-Defined Functions
- Contents
- About user-defined functions
- Creating user-defined functions
- Calling user-defined functions
- Working with arguments and variables in functions
- Handling errors in UDFs
- A user-defined function example
- Using UDFs effectively
- Building and Using ColdFusion Components
- Contents
- About ColdFusion components
- Creating ColdFusion components
- Using ColdFusion components
- Passing parameters to methods
- CFC variables and scope
- Using CFCs effectively
- ColdFusion component example
- Creating and Using Custom CFML Tags
- Building Custom CFXAPI Tags
- Developing CFML Applications
- Designing and Optimizing a ColdFusion Application
- Contents
- About applications
- Elements of a ColdFusion application
- Structuring an application
- Defining the application and its event handlers in Application.cfc
- Migrating from Application.cfm to Application.cfc
- Using an Application.cfm page
- Optimizing ColdFusion applications
- Handling Errors
- Contents
- About error handling in ColdFusion
- Understanding errors
- Error messages and the standard error format
- Determining error-handling strategies
- Specifying custom error messages with the cferror tag
- Logging errors with the cflog tag
- Handling runtime exceptions with ColdFusion tags
- Using Persistent Data and Locking
- Contents
- About persistent scope variables
- Managing the client state
- Configuring and using client variables
- Configuring and using session variables
- Configuring and using application variables
- Using server variables
- Locking code with cflock
- Examples of cflock
- Securing Applications
- Contents
- ColdFusion security features
- About resource and sandbox security
- About user security
- Using ColdFusion security tags and functions
- Security scenarios
- Implementing user security
- Developing Globalized Applications
- Debugging and Troubleshooting Applications
- Contents
- Configuring debugging in the ColdFusion MX Administrator
- Using debugging information from browser pages
- Controlling debugging information in CFML
- Using the cftrace tag to trace execution
- Using the cftimer tag to time blocks of code
- Using the Code Compatibility Analyzer
- Troubleshooting common problems
- Designing and Optimizing a ColdFusion Application
- Accessing and Using Data
- Introduction to Databases and SQL
- Accessing and Retrieving Data
- Updating Your Database
- Using Query of Queries
- Contents
- About record sets
- About Query of Queries
- Query of Queries user guide
- Using dot notation
- Using joins
- Using unions
- Using conditional operators
- Managing data types for columns
- Using the CAST function
- Using aggregate functions
- Using group by and having expressions
- Using ORDER BY clauses
- Using aliases
- Handling null values
- Concatenating strings
- Escaping reserved keywords
- Using Queries of Queries with dates
- Understanding Query of Queries performance
- Understanding Query of Queries processing
- Managing LDAP Directories
- Building a Search Interface
- Contents
- About Verity
- Creating a search tool for ColdFusion applications
- Creating a search page
- Enhancing search results
- Working with data returned from a query
- Using Verity Search Expressions
- Requesting and Presenting Information
- Introduction to Retrieving and Formatting Data
- Building Dynamic Forms with cfform Tags
- Validating Data
- Contents
- About ColdFusion MX validation
- Validating form fields
- Handling invalid data
- Masking form input values
- Validating form data with regular expressions
- Validating form data using hidden fields
- Validating form input and handling errors with JavaScript
- Validating data with the IsValid function and the cfparam tag
- Creating Forms in Macromedia Flash
- Creating Skinnable XML Forms
- Creating Charts and Graphs
- Creating Reports for Printing
- Contents
- About printable output
- Creating PDF and FlashPaper output with the cfdocument tag
- Creating reports with the ColdFusion MX 7 reporting
- Reporting features
- Reporting architecture
- Getting started
- Basic steps for creating reports
- Report definition guidelines
- Common reporting tasks and techniques
- Grouping and group breaks
- Defining, modifying, and using fields and input parameters
- Using toolbox elements on report bands
- Aligning elements
- Using text styles
- Previewing reports
- Displaying page numbers
- Using layered controls
- Using links
- Using the Properties sheet
- Displaying reports
- Using input parameters to pass variables and other data at runtime
- Configuring RDS
- Using the Report Creation Wizard
- Using the Query Builder
- Using CFML in reports
- Using charts
- Using subreports
- Font management with printable reports
- Creating reports with Crystal Reports (Windows only)
- Using the Flash Remoting Service
- Using Server-Side ActionScript
- Contents
- About server-side ActionScript
- Connecting to the Flash Remoting service
- Using server-side ActionScript functions
- Global and request scope objects
- About the CF.query function and data sources
- Using the CF.query function
- Building a simple application
- About the CF.http function
- Using the CF.http function
- Using Web Elements and External Objects
- Using XML and WDDX
- Contents
- About XML and ColdFusion
- The XML document object
- ColdFusion XML tag and functions
- Using an XML object
- Creating and saving an XML document object
- Modifying a ColdFusion XML object
- Validating XML documents
- Transforming documents with XSLT
- Extracting data with XPath
- Example: using XML in a ColdFusion application
- Moving complex data across the web with WDDX
- Using WDDX
- Using Web Services
- Contents
- Web services
- Working with WSDL files
- Consuming web services
- About the examples in this section
- Passing parameters to a web service
- Handling return values from a web service
- Using cfinvoke to consume a web service
- Using CFScript to consume a web service
- Consuming web services that are not generated by Macromedia ColdFusion MX
- Calling web services from a Macromedia Flash client
- Catching errors when consuming web services
- Handling inout and out parameters
- Configuring web services in the ColdFusion MX Administrator
- Data conversions between ColdFusion and WSDL data types
- Consuming ColdFusion web services
- Publishing web services
- Using request and response headers
- Handling complex data types
- Troubleshooting SOAP requests and responses
- Integrating J2EE and Java Elements in CFML Applications
- Integrating COM and CORBA Objects in CFML Applications
- Contents
- About COM and CORBA
- Creating and using objects
- Getting started with COM and DCOM
- Creating and using COM objects
- Getting started with CORBA
- Creating and using CORBA objects
- CORBA example
- Using XML and WDDX
- Using External Resources
- Sending and Receiving E-Mail
- Interacting with Remote Servers
- Managing Files on the Server
- Using Event Gateways
- Contents
- About event gateways
- Event gateway facilities and tools
- Structure of an event gateway application
- Configuring an event gateway instance
- Developing an event gateway application
- Deploying event gateways and applications
- Using the CFML event gateway for asynchronous CFCs
- Using the example event gateways and gateway applications
- Using the Instant Messaging Event Gateways
- Using the SMS Event Gateway
- Creating Custom Event Gateways
- Index

452 Chapter 19: Introduction to Databases and SQL
A bank might use a transaction to encapsulate a transfer from one account to another. For
example, if you transfer money from your savings account to your checking account, you do not
want the bank to debit the balance of your savings account unless it also credits your checking
account. If the update to the checking account fails, the bank can rollback the debit of the savings
account as part of the transaction.
ColdFusion MX includes the
cftransaction tag that lets you implement database transactions
for controlling rollback and commit. For more information, see CFML Reference.
Database design guidelines
From this basic description, the following database design rules emerge:
• Each record should contain a unique identifier as the primary key such as an employee ID, a
part number, or a customer number. The primary key is typically the column used to maintain
each record's unique identity among the tables in a relational database. Databases allow you to
use multiple columns for the primary key.
• When you define a column, you define a SQL data type for the column, such as allowing only
numeric values to be entered in the salary column.
• Assessing user needs and incorporating those needs in the database design is essential to a
successful implementation. A well-designed database accommodates the changing data needs
within an organization.
The best way to familiarize yourself with the capabilities of your database product or database
management system (DBMS) is to review the product documentation.
Using SQL
This section introduces SQL, describes basic SQL syntax, and contains examples of SQL
statements. It provides enough information for you to begin using ColdFusion MX. However,
this section does not contain an exhaustive description of the entire SQL programming language.
For complete SQL information, see the SQL reference that ships with your database.
A query is a request to a database. The query can ask for information from the database, write
new data to the database, update existing information in the database, or delete records from
the database.
Structured Query Language (SQL) is an ANSI/ISO standard programming language for writing
database queries. All databases supported by ColdFusion support SQL, and all ColdFusion tags
that access a database allow you to pass SQL statements to the tag.
SQL example
The most commonly used SQL statement in ColdFusion is the SELECT statement. The
SELECT statement reads data from a database and returns it to ColdFusion. For example, the
following SQL statement reads all the records from the employees table:
SELECT * FROM employees
You interpret this statement as "Select all rows from the table employees" where the wildcard
symbol (*) corresponds to all columns.