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HBase学习——4.HBase过滤器

1.过滤器

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。

1.1 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

1.2 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

2.HBase过滤器的分类

2.1 比较过滤器

2.1.1 行键过滤器 RowFilter

Filter rowFilter = new RowFilter(CompareOp.GREATER, new BinaryComparator("95007".getBytes()));

scan.setFilter(rowFilter);

public class HbaseFilterTest {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        Filter rowFilter = new RowFilter(CompareOp.GREATER, new BinaryComparator("95007".getBytes()));

        scan.setFilter(rowFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(cell);

            }

        }

    }

}

运行结果部分截图


 

2.1.2 列簇过滤器 FamilyFilter

Filter familyFilter = new FamilyFilter(CompareOp.EQUAL, new BinaryComparator("info".getBytes()));

scan.setFilter(familyFilter);

public class HbaseFilterTest {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        Filter familyFilter = new FamilyFilter(CompareOp.EQUAL, new BinaryComparator("info".getBytes()));

        scan.setFilter(familyFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(cell);

            }

        }

    }

}


 

2.1.3 列过滤器 QualifierFilter

Filter qualifierFilter = new QualifierFilter(CompareOp.EQUAL, new BinaryComparator("name".getBytes()));

scan.setFilter(qualifierFilter);

public class HbaseFilterTest {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        Filter qualifierFilter = new QualifierFilter(CompareOp.EQUAL, new BinaryComparator("name".getBytes()));

        scan.setFilter(qualifierFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(cell);

            }

        }

    }

}


 

2.1.4 值过滤器 ValueFilter

Filter valueFilter = new ValueFilter(CompareOp.EQUAL, new SubstringComparator("男"));

scan.setFilter(valueFilter);

public class HbaseFilterTest {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        Filter valueFilter = new ValueFilter(CompareOp.EQUAL, new SubstringComparator("男"));

        scan.setFilter(valueFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(cell);

            }

        }

    }

}


 

2.1.5 时间戳过滤器 TimestampsFilter

List<Long> list = new ArrayList<>();

list.add(1522469029503l);

TimestampsFilter timestampsFilter = new TimestampsFilter(list);

scan.setFilter(timestampsFilter);

public class HbaseFilterTest {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        List<Long> list = new ArrayList<>();

        list.add(1522469029503l);

        TimestampsFilter timestampsFilter = new TimestampsFilter(list);

        scan.setFilter(timestampsFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(Bytes.toString(cell.getRow()) + "\t" + Bytes.toString(cell.getFamily()) + "\t" + Bytes.toString(cell.getQualifier())

                + "\t" + Bytes.toString(cell.getValue()) + "\t" + cell.getTimestamp());

            }

        }

    }

}


 

2.2 专用过滤器

2.2.1 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);

public class HbaseFilterTest2 {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        SingleColumnValueFilter singleColumnValueFilter = new SingleColumnValueFilter(

                "info".getBytes(),

                "name".getBytes(),

                CompareOp.EQUAL,

                new SubstringComparator("刘晨"));

        singleColumnValueFilter.setFilterIfMissing(true);

        scan.setFilter(singleColumnValueFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(Bytes.toString(cell.getRow()) + "\t" + Bytes.toString(cell.getFamily()) + "\t" + Bytes.toString(cell.getQualifier())

                + "\t" + Bytes.toString(cell.getValue()) + "\t" + cell.getTimestamp());

            }

        }

    }

}


 

2.2.2 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);

public class HbaseFilterTest2 {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        SingleColumnValueExcludeFilter singleColumnValueExcludeFilter = new SingleColumnValueExcludeFilter(

                "info".getBytes(),

                "name".getBytes(),

                CompareOp.EQUAL,

                new SubstringComparator("刘晨"));

        singleColumnValueExcludeFilter.setFilterIfMissing(true);

        scan.setFilter(singleColumnValueExcludeFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(Bytes.toString(cell.getRow()) + "\t" + Bytes.toString(cell.getFamily()) + "\t" + Bytes.toString(cell.getQualifier())

                + "\t" + Bytes.toString(cell.getValue()) + "\t" + cell.getTimestamp());

            }

        }

    }

}


 

2.2.3 前缀过滤器 PrefixFilter----针对行键

PrefixFilter prefixFilter = new PrefixFilter("9501".getBytes());

scan.setFilter(prefixFilter);

public class HbaseFilterTest2 {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        PrefixFilter prefixFilter = new PrefixFilter("9501".getBytes());

        scan.setFilter(prefixFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(Bytes.toString(cell.getRow()) + "\t" + Bytes.toString(cell.getFamily()) + "\t" + Bytes.toString(cell.getQualifier())

                + "\t" + Bytes.toString(cell.getValue()) + "\t" + cell.getTimestamp());

            }

        }

    }

}


 

2.2.4 列前缀过滤器 ColumnPrefixFilter

ColumnPrefixFilter columnPrefixFilter = new ColumnPrefixFilter("name".getBytes());

scan.setFilter(columnPrefixFilter);

public class HbaseFilterTest2 {

    private static final String ZK_CONNECT_KEY = "hbase.zookeeper.quorum";

    private static final String ZK_CONNECT_VALUE = "hadoop1:2181,hadoop2:2181,hadoop3:2181";

    private static Connection conn = null;

    private static Admin admin = null;

    public static void main(String[] args) throws Exception {

        Configuration conf = HBaseConfiguration.create();

        conf.set(ZK_CONNECT_KEY, ZK_CONNECT_VALUE);

        conn = ConnectionFactory.createConnection(conf);

        admin = conn.getAdmin();

        Table table = conn.getTable(TableName.valueOf("student"));

        Scan scan = new Scan();

        ColumnPrefixFilter columnPrefixFilter = new ColumnPrefixFilter("name".getBytes());

        scan.setFilter(columnPrefixFilter);

        ResultScanner resultScanner = table.getScanner(scan);

        for(Result result : resultScanner) {

            List<Cell> cells = result.listCells();

            for(Cell cell : cells) {

                System.out.println(Bytes.toString(cell.getRow()) + "\t" + Bytes.toString(cell.getFamily()) + "\t" + Bytes.toString(cell.getQualifier())

                + "\t" + Bytes.toString(cell.getValue()) + "\t" + cell.getTimestamp());

            }

        }

    }

}


 

 


 
posted @ 2019-04-27 19:36  王知无  阅读(306)  评论(0编辑  收藏  举报