ColdFusion provides several variable scopes in which data persists past the life of a single request. These are the Client, Application, Session, and Server scopes. These scopes let you save data over time and share data between pages and even applications. These scopes as persistent scopes. In particular, you can use the Client and Session scopes to maintain information about a user across multiple requests.

ColdFusion lets you lock access to sections of code to ensure that ColdFusion does not attempt to run the code, or access the data that it uses, simultaneously or in an unpredictable order. This locking feature is important for ensuring the consistency of all shared data, including data in external sources in addition to data in persistent scopes.

You can use persistent scopes to develop an application and use locking to ensure data consistency.

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