问题描述:Bigtable的CellsColumnLimitFilter和ValueRangeFilter无法按预期工作,需要给出解决方法。
解决方法:
以下是一个使用CellsColumnLimitFilter和ValueRangeFilter的示例代码:
import com.google.cloud.bigtable.hbase.BigtableConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.CompareFilter;
import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
import org.apache.hadoop.hbase.util.Bytes;
public class BigtableFilterExample {
private static final String PROJECT_ID = "your-project-id";
private static final String INSTANCE_ID = "your-instance-id";
private static final String TABLE_NAME = "your-table-name";
private static final String COLUMN_FAMILY = "cf";
private static final String COLUMN_NAME = "col";
public static void main(String[] args) throws Exception {
Connection connection = BigtableConfiguration.connect(PROJECT_ID, INSTANCE_ID);
Table table = connection.getTable(TableName.valueOf(TABLE_NAME));
// 创建CellsColumnLimitFilter,限制每个列族最多返回3个Cell
Filter cellsColumnLimitFilter = new CellsColumnLimitFilter(3);
// 创建ValueRangeFilter,限制列值范围在[0, 100]之间
Filter valueRangeFilter = new ValueRangeFilter(Bytes.toBytes(0), true, Bytes.toBytes(100), true);
Scan scan = new Scan();
scan.addFamily(Bytes.toBytes(COLUMN_FAMILY));
scan.setFilter(new FilterList(cellsColumnLimitFilter, valueRangeFilter));
ResultScanner scanner = table.getScanner(scan);
for (Result result : scanner) {
for (Cell cell : result.listCells()) {
byte[] value = cell.getValueArray();
System.out.println("Value: " + Bytes.toString(value));
}
}
table.close();
connection.close();
}
}
请确保替换示例中的"your-project-id"、"your-instance-id"和"your-table-name"为实际的项目ID、实例ID和表名。
在示例代码中,通过scan.addFamily(Bytes.toBytes(COLUMN_FAMILY))
设置了列族,byte[] value = cell.getValueArray();
获取了列值。请确保这些值与实际的Bigtable表结构和数据一致。
如果CellsColumnLimitFilter和ValueRangeFilter没有返回预期的结果,可能是因为Bigtable表中不存在符合筛选条件的数据。请确保表中存在符合筛选条件的数据,并且列族、列名称和值范围设置正确。
通过以上方法,您应该可以解决Bigtable的CellsColumnLimitFilter和ValueRangeFilter无法按预期工作的问题。