过滤器(Filter)
基础API中的查询操作在面对大量数据的时候是非常苍白的,这里Hbase提供了高级的查询方法:Filter。Filter可以根据簇、列、版本等更多的条件来对数据进行过滤,基于Hbase本身提供的三维有序(主键有序、列有序、版本有序),这些Filter可以高效的完成查询过滤的任务。带有Filter条件的RPC查询请求会把Filter分发到各个RegionServer,是一个服务器端(Server-side)的过滤器,这样也可以降低网络传输的压力。
要完成一个过滤的操作,至少需要两个参数。一个是抽象的操作符,Hbase提供了枚举类型的变量来表示这些抽象的操作符:LESS/LESS_OR_EQUAL/EQUAL/NOT_EUQAL等;另外一个就是具体的比较器(Comparator),代表具体的比较逻辑,如果可以提高字节级的比较、字符串级的比较等。有了这两个参数,我们就可以清晰的定义筛选的条件,过滤数据。
抽象操作符(比较运算符)
LESS <
LESS_OR_EQUAL <=
EQUAL =
NOT_EQUAL <>
GREATER_OR_EQUAL >=
GREATER >
NO_OP 排除所有
比较器(指定比较机制)
BinaryComparator 按字节索引顺序比较指定字节数组,采用 Bytes.compareTo(byte[])
BinaryPrefixComparator 跟前面相同,只是比较左端的数据是否相同
NullComparator 判断给定的是否为空
BitComparator 按位比较
RegexStringComparator 提供一个正则的比较器,仅支持 EQUAL 和非 EQUAL
SubstringComparator 判断提供的子串是否出现在 value 中
HBase过滤器的分类
比较过滤器
1、行键过滤器 RowFilter
Filter rowFilter = new RowFilter(CompareOp.GREATER, new BinaryComparator("95007".getBytes())); scan.setFilter(rowFilter);
1 public class HbaseFilterTest { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 Filter rowFilter = new RowFilter(CompareOp.GREATER, new BinaryComparator("95007".getBytes())); 20 scan.setFilter(rowFilter); 21 ResultScanner resultScanner = table.getScanner(scan); 22 for(Result result : resultScanner) { 23 List<Cell> cells = result.listCells(); 24 for(Cell cell : cells) { 25 System.out.println(cell); 26 } 27 } 28 29 30 }
运行结果部分截图
2、列簇过滤器 FamilyFilter
Filter familyFilter = new FamilyFilter(CompareOp.EQUAL, new BinaryComparator("info".getBytes())); scan.setFilter(familyFilter);
1 public class HbaseFilterTest { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 Filter familyFilter = new FamilyFilter(CompareOp.EQUAL, new BinaryComparator("info".getBytes())); 20 scan.setFilter(familyFilter); 21 ResultScanner resultScanner = table.getScanner(scan); 22 for(Result result : resultScanner) { 23 List<Cell> cells = result.listCells(); 24 for(Cell cell : cells) { 25 System.out.println(cell); 26 } 27 } 28 29 30 } 31 32 33 }
3、列过滤器 QualifierFilter
Filter qualifierFilter = new QualifierFilter(CompareOp.EQUAL, new BinaryComparator("name".getBytes())); scan.setFilter(qualifierFilter);
1 public class HbaseFilterTest { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 Filter qualifierFilter = new QualifierFilter(CompareOp.EQUAL, new BinaryComparator("name".getBytes())); 20 scan.setFilter(qualifierFilter); 21 ResultScanner resultScanner = table.getScanner(scan); 22 for(Result result : resultScanner) { 23 List<Cell> cells = result.listCells(); 24 for(Cell cell : cells) { 25 System.out.println(cell); 26 } 27 } 28 29 30 } 31 32 33 }
4、值过滤器 ValueFilter
Filter valueFilter = new ValueFilter(CompareOp.EQUAL, new SubstringComparator("男")); scan.setFilter(valueFilter);
1 public class HbaseFilterTest { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 Filter valueFilter = new ValueFilter(CompareOp.EQUAL, new SubstringComparator("男")); 20 scan.setFilter(valueFilter); 21 ResultScanner resultScanner = table.getScanner(scan); 22 for(Result result : resultScanner) { 23 List<Cell> cells = result.listCells(); 24 for(Cell cell : cells) { 25 System.out.println(cell); 26 } 27 } 28 29 30 } 31 32 33 }
5、时间戳过滤器 TimestampsFilter
List<Long> list = new ArrayList<>(); list.add(1522469029503l); TimestampsFilter timestampsFilter = new TimestampsFilter(list); scan.setFilter(timestampsFilter);
1 public class HbaseFilterTest { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 List<Long> list = new ArrayList<>(); 20 list.add(1522469029503l); 21 TimestampsFilter timestampsFilter = new TimestampsFilter(list); 22 scan.setFilter(timestampsFilter); 23 ResultScanner resultScanner = table.getScanner(scan); 24 for(Result result : resultScanner) { 25 List<Cell> cells = result.listCells(); 26 for(Cell cell : cells) { 27 System.out.println(Bytes.toString(cell.getRow()) + "/t" + Bytes.toString(cell.getFamily()) + "/t" + Bytes.toString(cell.getQualifier()) 28 + "/t" + Bytes.toString(cell.getValue()) + "/t" + cell.getTimestamp()); 29 } 30 } 31 32 33 } 34 35 36 }
专用过滤器
1、单列值过滤器 SingleColumnValueFilter —-会返回满足条件的整行
SingleColumnValueFilter singleColumnValueFilter = new SingleColumnValueFilter( "info".getBytes(), //列簇 "name".getBytes(), //列 CompareOp.EQUAL, new SubstringComparator("刘晨")); //如果不设置为 true,则那些不包含指定 column 的行也会返回 singleColumnValueFilter.setFilterIfMissing(true); scan.setFilter(singleColumnValueFilter);
1 public class HbaseFilterTest2 { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 SingleColumnValueFilter singleColumnValueFilter = new SingleColumnValueFilter( 20 "info".getBytes(), 21 "name".getBytes(), 22 CompareOp.EQUAL, 23 new SubstringComparator("刘晨")); 24 singleColumnValueFilter.setFilterIfMissing(true); 25 26 scan.setFilter(singleColumnValueFilter); 27 ResultScanner resultScanner = table.getScanner(scan); 28 for(Result result : resultScanner) { 29 List<Cell> cells = result.listCells(); 30 for(Cell cell : cells) { 31 System.out.println(Bytes.toString(cell.getRow()) + "/t" + Bytes.toString(cell.getFamily()) + "/t" + Bytes.toString(cell.getQualifier()) 32 + "/t" + Bytes.toString(cell.getValue()) + "/t" + cell.getTimestamp()); 33 } 34 } 35 36 37 } 38 39 40 }
2、单列值排除器 SingleColumnValueExcludeFilter
SingleColumnValueExcludeFilter singleColumnValueExcludeFilter = new SingleColumnValueExcludeFilter( "info".getBytes(), "name".getBytes(), CompareOp.EQUAL, new SubstringComparator("刘晨")); singleColumnValueExcludeFilter.setFilterIfMissing(true); scan.setFilter(singleColumnValueExcludeFilter);
1 public class HbaseFilterTest2 { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 SingleColumnValueExcludeFilter singleColumnValueExcludeFilter = new SingleColumnValueExcludeFilter( 20 "info".getBytes(), 21 "name".getBytes(), 22 CompareOp.EQUAL, 23 new SubstringComparator("刘晨")); 24 singleColumnValueExcludeFilter.setFilterIfMissing(true); 25 26 scan.setFilter(singleColumnValueExcludeFilter); 27 ResultScanner resultScanner = table.getScanner(scan); 28 for(Result result : resultScanner) { 29 List<Cell> cells = result.listCells(); 30 for(Cell cell : cells) { 31 System.out.println(Bytes.toString(cell.getRow()) + "/t" + Bytes.toString(cell.getFamily()) + "/t" + Bytes.toString(cell.getQualifier()) 32 + "/t" + Bytes.toString(cell.getValue()) + "/t" + cell.getTimestamp()); 33 } 34 } 35 36 37 } 38 39 40 }
3、前缀过滤器 PrefixFilter—-针对行键
PrefixFilter prefixFilter = new PrefixFilter("9501".getBytes()); scan.setFilter(prefixFilter);
1 public class HbaseFilterTest2 { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 PrefixFilter prefixFilter = new PrefixFilter("9501".getBytes()); 20 21 scan.setFilter(prefixFilter); 22 ResultScanner resultScanner = table.getScanner(scan); 23 for(Result result : resultScanner) { 24 List<Cell> cells = result.listCells(); 25 for(Cell cell : cells) { 26 System.out.println(Bytes.toString(cell.getRow()) + "/t" + Bytes.toString(cell.getFamily()) + "/t" + Bytes.toString(cell.getQualifier()) 27 + "/t" + Bytes.toString(cell.getValue()) + "/t" + cell.getTimestamp()); 28 } 29 } 30 31 32 } 33 34 35 }
4、列前缀过滤器 ColumnPrefixFilter
ColumnPrefixFilter columnPrefixFilter = new ColumnPrefixFilter("name".getBytes()); scan.setFilter(columnPrefixFilter);
1 public class HbaseFilterTest2 { 2 3 private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum"; 4 private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181"; 5 6 private static Connection conn = null; 7 private static Admin admin = null; 8 9 public static void main(String[] args) throws Exception { 10 11 Configuration conf = HBaseConfiguration.create(); 12 conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE); 13 conn = ConnectionFactory.createConnection(conf); 14 admin = conn.getAdmin(); 15 Table table = conn.getTable(TableName.valueOf("student")); 16 17 Scan scan = new Scan(); 18 19 ColumnPrefixFilter columnPrefixFilter = new ColumnPrefixFilter("name".getBytes()); 20 21 scan.setFilter(columnPrefixFilter); 22 ResultScanner resultScanner = table.getScanner(scan); 23 for(Result result : resultScanner) { 24 List<Cell> cells = result.listCells(); 25 for(Cell cell : cells) { 26 System.out.println(Bytes.toString(cell.getRow()) + "/t" + Bytes.toString(cell.getFamily()) + "/t" + Bytes.toString(cell.getQualifier()) 27 + "/t" + Bytes.toString(cell.getValue()) + "/t" + cell.getTimestamp()); 28 } 29 } 30 31 32 } 33 34 35 }
5、分页过滤器 PageFilter
原创文章,作者:Maggie-Hunter,如若转载,请注明出处:https://blog.ytso.com/tech/bigdata/9010.html