前言:本文詳細介紹了 HBase QualifierFilter 過濾器 Java&Shell API 的使用,並貼出了相關示例代碼以供參考。QualifierFilter 基於列名進行過濾,在工做中涉及到須要經過HBase 列名進行數據過濾時能夠考慮使用它。比較器細節及原理請參照以前的更文:HBase Filter 過濾器之比較器 Comparator 原理及源碼學習java
頭部代碼git
/** * 用於列名(Qualifier)過濾。 */ public class QualifierFilterDemo { private static boolean isok = false; private static String tableName = "test"; private static String[] cfs = new String[]{"f"}; private static String[] data = new String[]{ "row-1:f:name:Wang", "row-1:f:age:20", "row-2:f:name:Zhou", "row-2:f:age:10", "row-3:f:gender:男", "row-3:f:name:Li", "row-4:f:namana:xyz", "row-4:f:age:Zhao" }; public static void main(String[] args) throws IOException { MyBase myBase = new MyBase(); Connection connection = myBase.createConnection(); if (isok) { myBase.deleteTable(connection, tableName); myBase.createTable(connection, tableName, cfs); // 造數據 myBase.putRows(connection, tableName, data); } Table table = connection.getTable(TableName.valueOf(tableName)); Scan scan = new Scan();
中部代碼
向右滑動滾動條可查看輸出結果。github
QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes("age"))); // [row-1:f:age, row-2:f:age, row-4:f:age] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.NOT_EQUAL, new BinaryComparator(Bytes.toBytes("name"))); // [row-1:f:age, row-2:f:age, row-3:f:gender, row-4:f:age, row-4:f:namana] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.GREATER, new BinaryComparator(Bytes.toBytes("gender"))); // [row-1:f:name, row-2:f:name, row-3:f:name, row-4:f:namana] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.GREATER_OR_EQUAL, new BinaryComparator(Bytes.toBytes("name"))); // [row-1:f:name, row-2:f:name, row-3:f:name] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.LESS, new BinaryComparator(Bytes.toBytes("gender"))); // [row-1:f:age, row-2:f:age, row-4:f:age] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryComparator(Bytes.toBytes("gender"))); // [row-1:f:age, row-2:f:age, row-3:f:gender, row-4:f:age]
QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes("nam"))); // [row-1:f:name, row-2:f:name, row-3:f:name, row-4:f:namana] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.NOT_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("nam"))); // [row-1:f:age, row-2:f:age, row-3:f:gender, row-4:f:age] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.GREATER, new BinaryPrefixComparator(Bytes.toBytes("g"))); // [row-1:f:name, row-2:f:name, row-3:f:name, row-4:f:namana] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.GREATER_OR_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("n"))); // [row-1:f:name, row-2:f:name, row-3:f:name, row-4:f:namana] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.LESS, new BinaryPrefixComparator(Bytes.toBytes("m"))); // [row-1:f:age, row-2:f:age, row-3:f:gender, row-4:f:age] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("a"))); // [row-1:f:age, row-2:f:age, row-4:f:age]
QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.EQUAL, new SubstringComparator("g")); // [row-1:f:age, row-2:f:age, row-3:f:gender, row-4:f:age] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.NOT_EQUAL, new SubstringComparator("n")); // [row-1:f:age, row-2:f:age, row-4:f:age]
QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.NOT_EQUAL, new RegexStringComparator("nam")); // [row-1:f:age, row-2:f:age, row-3:f:gender, row-4:f:age] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator("nam")); // [row-1:f:name, row-2:f:name, row-3:f:name, row-4:f:namana] QualifierFilter qualifierFilter = new QualifierFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator("n[a-z]m")); // [row-1:f:name, row-2:f:name, row-3:f:name, row-4:f:namana]
尾部代碼shell
scan.setFilter(qualifierFilter); ResultScanner scanner = table.getScanner(scan); Iterator<Result> iterator = scanner.iterator(); LinkedList<String> rowkeys = new LinkedList<>(); while (iterator.hasNext()) { Result result = iterator.next(); String rowkey = Bytes.toString(result.getRow()); rowkeys.add(rowkey); } System.out.println(rowkeys); scanner.close(); table.close(); connection.close(); } }
方式一:apache
hbase(main):003:0> scan 'test',{FILTER=>"QualifierFilter(=,'binary:age')"} ROW COLUMN+CELL row-1 column=f:age, timestamp=1589252853542, value=20 row-2 column=f:age, timestamp=1589252853542, value=10 row-4 column=f:age, timestamp=1589252853542, value=Zhao 3 row(s) in 0.0680 seconds
支持的比較運算符:= != > >= < <=,再也不一一舉例。api
方式二:微信
import org.apache.hadoop.hbase.filter.CompareFilter import org.apache.hadoop.hbase.filter.BinaryComparator import org.apache.hadoop.hbase.filter.QualifierFilter hbase(main):010:0> scan 'test',{FILTER => QualifierFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), BinaryComparator.new(Bytes.toBytes('age')))} ROW COLUMN+CELL row-1 column=f:age, timestamp=1589252853542, value=20 row-2 column=f:age, timestamp=1589252853542, value=10 row-4 column=f:age, timestamp=1589252853542, value=Zhao 3 row(s) in 0.0400 seconds
支持的比較運算符:LESS、LESS_OR_EQUAL、EQUAL、NOT_EQUAL、GREATER、GREATER_OR_EQUAL,再也不一一舉例。oop
推薦使用方式一,更簡潔方便。學習
方式一:code
hbase(main):011:0> scan 'test',{FILTER=>"QualifierFilter(=,'binaryprefix:nam')"} ROW COLUMN+CELL row-1 column=f:name, timestamp=1589252853542, value=Wang row-2 column=f:name, timestamp=1589252853542, value=Zhou row-3 column=f:name, timestamp=1589252853542, value=Li row-4 column=f:namana, timestamp=1589252853542, value=xyz 4 row(s) in 0.0410 seconds
方式二:
import org.apache.hadoop.hbase.filter.CompareFilter import org.apache.hadoop.hbase.filter.BinaryPrefixComparator import org.apache.hadoop.hbase.filter.QualifierFilter hbase(main):014:0> scan 'test',{FILTER => QualifierFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), BinaryPrefixComparator.new(Bytes.toBytes('nam')))} ROW COLUMN+CELL row-1 column=f:name, timestamp=1589252853542, value=Wang row-2 column=f:name, timestamp=1589252853542, value=Zhou row-3 column=f:name, timestamp=1589252853542, value=Li row-4 column=f:namana, timestamp=1589252853542, value=xyz 4 row(s) in 0.0200 seconds
其它同上。
方式一:
hbase(main):015:0> scan 'test',{FILTER=>"QualifierFilter(=,'substring:am')"} ROW COLUMN+CELL row-1 column=f:name, timestamp=1589252853542, value=Wang row-2 column=f:name, timestamp=1589252853542, value=Zhou row-3 column=f:name, timestamp=1589252853542, value=Li row-4 column=f:namana, timestamp=1589252853542, value=xyz 4 row(s) in 0.0230 seconds
方式二:
import org.apache.hadoop.hbase.filter.CompareFilter import org.apache.hadoop.hbase.filter.SubstringComparator import org.apache.hadoop.hbase.filter.QualifierFilter hbase(main):017:0> scan 'test',{FILTER => QualifierFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), SubstringComparator.new('am'))} ROW COLUMN+CELL row-1 column=f:name, timestamp=1589252853542, value=Wang row-2 column=f:name, timestamp=1589252853542, value=Zhou row-3 column=f:name, timestamp=1589252853542, value=Li row-4 column=f:namana, timestamp=1589252853542, value=xyz 4 row(s) in 0.0220 seconds
區別於上的是這裏直接傳入字符串進行比較,且只支持EQUAL和NOT_EQUAL兩種比較符。
import org.apache.hadoop.hbase.filter.CompareFilter import org.apache.hadoop.hbase.filter.RegexStringComparator import org.apache.hadoop.hbase.filter.QualifierFilter hbase(main):019:0> scan 'test',{FILTER => QualifierFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), RegexStringComparator.new('n[a-z]m'))} ROW COLUMN+CELL row-1 column=f:name, timestamp=1589252853542, value=Wang row-2 column=f:name, timestamp=1589252853542, value=Zhou row-3 column=f:name, timestamp=1589252853542, value=Li row-4 column=f:namana, timestamp=1589252853542, value=xyz 4 row(s) in 0.0250 seconds
該比較器直接傳入字符串進行比較,且只支持EQUAL和NOT_EQUAL兩種比較符。若想使用第一種方式能夠傳入regexstring試一下,個人版本有點低暫時不支持,再也不演示了。
注意這裏的正則匹配指包含關係,對應底層find()方法。
QualifierFilter 不支持使用LongComparator比較器,且BitComparator、NullComparator 比較器用之甚少,也再也不介紹。
查看文章所有源代碼請訪如下GitHub地址:
https://github.com/zhoupengbo/demos-bigdata/blob/master/hbase/hbase-filters-demos/src/main/java/com/zpb/demos/QualifierFilterDemo.java
轉載請註明出處!歡迎關注本人微信公衆號【HBase工做筆記】