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Interface DatastoreReader (2.20.2)
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public interface DatastoreReader
An interface to represent Google Cloud Datastore read operations.
Methods
<T>run(Query<T> query)
public abstract QueryResults<T> <T>run(Query<T> query)
Submits a Query and returns its result.
Parameter
Name
Description
query
Query <T >
fetch(Key[] keys)
public abstract List<Entity> fetch(Key[] keys)
Returns a list with a value for each given key (ordered by input). null
values are
returned for nonexistent keys. When possible prefer using #get(Key...) to avoid eagerly
loading the results.
Parameter
Name
Description
keys
Key []
get(Key key)
public abstract Entity get(Key key)
Returns an Entity for the given Key or null
if it doesn't exist.
Parameter
Name
Description
key
Key
Returns
Type
Description
Entity
get(Key[] keys)
public abstract Iterator<Entity> get(Key[] keys)
Returns an Entity for each given Key that exists in the Datastore. The order of
the result is unspecified. Results are loaded lazily, so it is possible to get a
DatastoreException
from the returned Iterator
's hasNext or
next methods.
See Also: #get(Key)
Parameter
Name
Description
keys
Key []
runAggregation(AggregationQuery query)
public default AggregationResults runAggregation(AggregationQuery query)
runAggregation(AggregationQuery query, ExplainOptions explainOptions)
public default AggregationResults runAggregation(AggregationQuery query, ExplainOptions explainOptions)
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Last updated 2024-07-09 UTC.
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