Class Query (2.20.1)

public final class Query implements Serializable

A simple wrapper to construct a query for the ReadRows RPC.

Inheritance

Object > Query

Implements

Serializable

Inherited Members

Object.clone()

Object.equals(Object)

Object.finalize()

Object.getClass()

Object.hashCode()

Object.notify()

Object.notifyAll()

Object.toString()

Object.wait()

Object.wait(long)

Object.wait(long,int)

Static Methods

create(String tableId)

public static Query create(String tableId)

Constructs a new Query object for the specified table id. The table id will be combined with the instance name specified in the com.google.cloud.bigtable.data.v2.BigtableDataSettings.

Parameter
Name	Description
`tableId`	`String`

Returns
Type	Description
`Query`

fromProto(ReadRowsRequest request)

public static Query fromProto(ReadRowsRequest request)

Wraps the protobuf ReadRowsRequest.

WARNING: Please note that the project id & instance id in the table name will be overwritten by the configuration in the BigtableDataClient.

Parameter
Name	Description
`request`	`com.google.bigtable.v2.ReadRowsRequest`

Returns
Type	Description
`Query`

Methods

clone()

public Query clone()

Returns
Type	Description
`Query`

Overrides

Object.clone()

createPaginator(int pageSize)

public Query.QueryPaginator createPaginator(int pageSize)

Create a query paginator that'll split the query into smaller chunks.

Example usage:


 Query query = Query.create(...).range("a", "z");
 Query.QueryPaginator paginator = query.createQueryPaginator(100);
 ByteString lastSeenRowKey = ByteString.EMPTY;
 do {
     List<Row> rows = client.readRowsCallable().all().call(paginator.getNextQuery());
     for (Row row : rows) {
        // do some processing
        lastSeenRow = row;
     }
 } while (paginator.advance(lastSeenRowKey));

Parameter
Name	Description
`pageSize`	`int`

Returns
Type	Description
`Query.QueryPaginator`

equals(Object o)

public boolean equals(Object o)

Parameter
Name	Description
`o`	`Object`

Returns
Type	Description
`boolean`

Overrides

Object.equals(Object)

filter(Filters.Filter filter)

public Query filter(Filters.Filter filter)

Sets the filter to apply to each row. Only one filter can be set at a time. To use multiple filters, please use Filters#interleave() or Filters#chain().

Parameter
Name	Description
`filter`	`Filters.Filter`

Returns
Type	Description
`Query`

getBound()

public Range.ByteStringRange getBound()

Get the minimal range that encloses all of the row keys and ranges in this Query.

Returns
Type	Description
`Range.ByteStringRange`

hashCode()

public int hashCode()

Returns
Type	Description
`int`

Overrides

Object.hashCode()

limit(long limit)

public Query limit(long limit)

Limits the number of rows that can be returned

Parameter
Name	Description
`limit`	`long`

Returns
Type	Description
`Query`

prefix(ByteString prefix)

public Query prefix(ByteString prefix)

Parameter
Name	Description
`prefix`	`ByteString`

Returns
Type	Description
`Query`

prefix(String prefix)

public Query prefix(String prefix)

Parameter
Name	Description
`prefix`	`String`

Returns
Type	Description
`Query`

range(Range.ByteStringRange range)

public Query range(Range.ByteStringRange range)

Adds a range to be looked up.

Parameter
Name	Description
`range`	`Range.ByteStringRange`

Returns
Type	Description
`Query`

range(ByteString start, ByteString end)

public Query range(ByteString start, ByteString end)

Adds a range to be looked up.

Parameters
Name	Description
`start`	`ByteString` The beginning of the range (inclusive). Can be null to represent negative infinity.
`end`	`ByteString` The end of the range (exclusive). Can be null to represent positive infinity.

Returns
Type	Description
`Query`

range(String start, String end)

public Query range(String start, String end)

Adds a range to be looked up.

Parameters
Name	Description
`start`	`String` The beginning of the range (inclusive). Can be null to represent negative infinity.
`end`	`String` The end of the range (exclusive). Can be null to represent positive infinity.

Returns
Type	Description
`Query`

rowKey(ByteString key)

public Query rowKey(ByteString key)

Adds a key to looked up

Parameter
Name	Description
`key`	`ByteString`

Returns
Type	Description
`Query`

rowKey(String key)

public Query rowKey(String key)

Adds a key to looked up

Parameter
Name	Description
`key`	`String`

Returns
Type	Description
`Query`

shard(List<KeyOffset> sampledRowKeys)

public List<Query> shard(List<KeyOffset> sampledRowKeys)

Split this query into multiple queries that can be evenly distributed across Bigtable nodes and be run in parallel. This method takes the results from com.google.cloud.bigtable.data.v2.BigtableDataClient#sampleRowKeysAsync(String) to divide this query into a set of disjoint queries that logically combine into form this query.

Expected Usage:


 List<KeyOffset> keyOffsets = dataClient.sampleRowKeysAsync("my-table").get();
 List<Query> queryShards = myQuery.shard(keyOffsets);
 List

Parameter
Name	Description
`sampledRowKeys`	`List<KeyOffset>`

Returns
Type	Description
`List<Query>`

shard(SortedSet<ByteString> splitPoints)

public List<Query> shard(SortedSet<ByteString> splitPoints)

Split this query into multiple queries that logically combine into this query. This is intended to be used by map reduce style frameworks like Beam to split a query across multiple workers.

Expected Usage:


 List<ByteString> splitPoints = ...;
 List<Query> queryShards = myQuery.shard(splitPoints);
 List

Parameter
Name	Description
`splitPoints`	`SortedSet<ByteString>`

Returns
Type	Description
`List<Query>`

toProto(RequestContext requestContext)

public ReadRowsRequest toProto(RequestContext requestContext)

Creates the request protobuf. This method is considered an internal implementation detail and not meant to be used by applications.

Parameter
Name	Description
`requestContext`	`com.google.cloud.bigtable.data.v2.internal.RequestContext`

Returns
Type	Description
`com.google.bigtable.v2.ReadRowsRequest`

toString()

public String toString()

Returns
Type	Description
`String`

Overrides

Object.toString()