Class StructuredQuery<V> (2.21.2)

An implementation of a Google Cloud Datastore Query that can be constructed by providing all the specific query elements.

A usage example:

A simple query that returns all entities for a specific kind

 Query<Entity> query = Query.newEntityQueryBuilder().setKind(kind).build();
 QueryResults<Entity> results = datastore.run(query);
 while (results.hasNext()) {
   Entity entity = results.next();
   ...
 }
 

A simple key-only query of all entities for a specific kind

 Query<Key> keyOnlyQuery =  Query.newKeyQueryBuilder().setKind(KIND1).build();
 QueryResults<Key> results = datastore.run(keyOnlyQuery);
 ...
 

A less trivial example of a projection query that returns the first 10 results of "age" and "name" properties (sorted and grouped by "age") with an age greater than 18

 Query<ProjectionEntity> query = Query.newProjectionEntityQueryBuilder()
     .setKind(kind)
     .setProjection(Projection.property("age"), Projection.first("name"))
     .setFilter(PropertyFilter.gt("age", 18))
     .setGroupBy("age")
     .setOrderBy(OrderBy.asc("age"))
     .setLimit(10)
     .build();
 QueryResults<ProjectionEntity> results = datastore.run(query);
 ...
 

See Also: Datastore queries

Returns the distinct on clause for this query.

Returns the end cursor for this query.

Returns the filter for this query.

Returns the kind for this query.

Returns the limit for this query.

Returns the offset for this query.

Returns the order by clause for this query.

Returns the projection for this query.

Returns the start cursor for this query.