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---- h1. Client-configurable Query Execution Parameters
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FQP 1.4 allows clients to configure the behavior of certain aspects of query processing. Clients may control behavior when queries to target data services fail:
# Clients may specify that partial results are acceptable
** For example, if the DCQL query hits 12 target data services and 5 error out, results from the 7 which worked are still returned.
# Number of retries and a timeout between connection attempts may be specified
** The Federated Query Processor service includes deploy-time configurable service properties which may limit the maximum number of retries to prevent malicious clients from overloading the service and tying up resources.
** For example, if the DCQL query hits 12 target data services and 5 error out, results from the 7 which worked are still returned.
# Number of retries and a timeout between connection attempts may be specified
** The Federated Query Processor service includes deploy-time configurable service properties which may limit the maximum number of retries to prevent malicious clients from overloading the service and tying up resources.
# Behavior when queries to target data services fail
## Clients may specify that partial results are acceptable
### For example, if the DCQL query hits 12 target data services and 5 error out, results from the 7 which worked are still returned.
## Number of retries and a timeout between connection attempts may be specified
### The Federated Query Processor service includes deploy-time configurable service properties which may limit the maximum number of retries to prevent malicious clients from overloading the service and tying up resources.
## Clients may specify that partial results are acceptable
### For example, if the DCQL query hits 12 target data services and 5 error out, results from the 7 which worked are still returned.
## Number of retries and a timeout between connection attempts may be specified
### The Federated Query Processor service includes deploy-time configurable service properties which may limit the maximum number of retries to prevent malicious clients from overloading the service and tying up resources.
h1. WS-Notification Support
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...# DCQLQuery query
## ** The query to execute.
# DelegatedCredentialReference delegatedCredential
## ** Optional parameter (may be null) which allows the client to delegate their credentials to the Federated Query Service which will be used when contacting data services involved in the DCQL query.
# QueryExecutionParameters executionParameters
## ** Optional parameter (may be null) which allows the client to control certain aspects of the query processor's behavior.
This method returns a Federated Query Results Reference, which can be used to retrieve the DCQL Query Results when processing is complete.
...The FQP results resource has several public methods, some of which are new for version 1.4.
# *getAggregateResults*: Aggregates the DCQL query results and returns them as a single CQLQueryResults instance.
# *getResults*: Returns the DCQLQueryResultsCollection generated by the query process.
# *isProcessingComplete*: Returns a boolean flag indicating if query processing is complete.
## In FQP 1.3, clients had to poll this method continuously to determine of a query was complete and results could be retrieved.
# *enumerate (new for 1.4)*: Allows the client to leverage WS-Enumeration to return results. Creates an enumeration context on the serer, and returns an EnumerationResponseContainer, a caGrid type which encapsulates an Endpoint Reference and Enumeration Context.
# *transfer (new for 1.4)*: Allows the client to leverage caGrid's Transfer service to return results. This creates the transfer data resource and returns a TransferServiceContextReference. This method can be used in conjunction with the caGrid Transfer tools to retrieve the data.