HBase学习之路 (六)过滤器
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);
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、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);
}
} } }
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);
}
} } }
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);
}
} } }
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());
}
} } }
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);
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、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());
}
} } }
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());
}
} } }
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());
}
} } }
5、分页过滤器 PageFilter
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