You can see the list of materialized views used for a particular query by looking at the Advanced Details window of the query's graphical plan in Interactive SQL. See Reading execution plans.
You can also use Application Profiling mode in Sybase Central to determine whether a materialized view was considered during the enumeration phase of a query, by looking at the access plans enumerated by the optimizer. To see the access plans enumerated by the optimizer, tracing must be turned on, and must be configured to include the OPTIMIZATION_LOGGING tracing type. For more information about this tracing type, see Application profiling, and Choosing a diagnostic tracing level.
For more information about the enumeration phase of optimization, see Query processing phases.
When snapshot isolation is in use, the optimizer does not consider materialized views that were refreshed after the start of the snapshot for the current transaction.
Discuss this page in DocCommentXchange.
|Copyright © 2010, iAnywhere Solutions, Inc. - SQL Anywhere 12.0.0|