Implementing parameterized queries
An Apama query can define parameters and then refer to those parameters throughout the query definition. This enables a query definition to function as a template for multiple query instances.
A query that defines parameters is referred to as a parameterized query. An instance of a parameterized query is referred to as a parameterization.
A parameterized query offers the following benefits:
Patterns of interest (
find patterns) may be customized from a single generic query. This can significantly reduce the amount of code that needs to be written and maintained.
Parameterizations exist only at runtime. There is no need to maintain a file for each instance.
Parameters can be used throughout the query in which they are defined. For example, you can use them in the definition of inputs, in
find actions, and in user-defined actions. Values do not need to be hardcoded.