com.google.api.services.datastore.client

Interface QuerySplitter

public interface QuerySplitter

Provides the ability to split a query into multiple shards.

Method Summary

Modifier and Type	Method and Description
List<DatastoreV1.Query>	getSplits(DatastoreV1.Query query, DatastoreV1.PartitionId partition, int numSplits, Datastore datastore) Returns a list of sharded DatastoreV1.Querys for the given query.
List<DatastoreV1.Query>	getSplits(DatastoreV1.Query query, int numSplits, Datastore datastore) Deprecated. Use getSplits(Query, PartitionId, int, Datastore) instead, which provides the ability to supply a namespace.

Method Detail

getSplits

@Deprecated
List<DatastoreV1.Query> getSplits(DatastoreV1.Query query,
                                              int numSplits,
                                              Datastore datastore)
                                       throws DatastoreException

Deprecated. Use getSplits(Query, PartitionId, int, Datastore) instead, which provides the ability to supply a namespace.

Returns a list of sharded DatastoreV1.Querys for the given query.

This will create up to the desired number of splits, however it may return less splits if the desired number of splits is unavailable. This will happen if the number of split points provided by the underlying Datastore is less than the desired number, which will occur if the number of results for the query is too small.

Parameters:

query - the query to split.

numSplits - the desired number of splits.

datastore - the datastore to run on.

Throws:

DatastoreException - if there was a datastore error while generating query splits.

IllegalArgumentException - if the given query or numSplits was invalid.

getSplits

List<DatastoreV1.Query> getSplits(DatastoreV1.Query query,
                                  DatastoreV1.PartitionId partition,
                                  int numSplits,
                                  Datastore datastore)
                           throws DatastoreException

Returns a list of sharded DatastoreV1.Querys for the given query.

This will create up to the desired number of splits, however it may return less splits if the desired number of splits is unavailable. This will happen if the number of split points provided by the underlying Datastore is less than the desired number, which will occur if the number of results for the query is too small.

Parameters:

query - the query to split.

partition - the partition to run in.

numSplits - the desired number of splits.

datastore - the datastore to run on.

Throws:

DatastoreException - if there was a datastore error while generating query splits.

IllegalArgumentException - if the given query or numSplits was invalid.