Query preparation determines how the AVM will access the requested data, for example, which indices to use. The compiler prepares statically opened queries at compile time. The AVM prepares dynamically opened queries at run time, using the QUERY-PREPARE() method.

Because preparation of a dynamically opened query can have an impact on performance, query information logging tracks the following statistics on dynamically opened queries:

• Number of times the AVM has prepared this query
• Time taken to prepare the query (in milliseconds)
• Database block access required to prepare the query