Interface DatastoreReader (2.32.2)
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 abstract AggregationResults runAggregation(AggregationQuery query)
runAggregation(AggregationQuery query, ExplainOptions explainOptions)
public abstract AggregationResults runAggregation(AggregationQuery query, ExplainOptions explainOptions)
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Last updated 2025-10-11 UTC.
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