HBase Filter 过滤器之QualifierFilter详解

前言:本文详细介绍了 HBase QualifierFilter 过滤器 Java&Shell API 的使用,并贴出了相关示例代码以供参考。QualifierFilter 基于列名进行过滤,在工作中涉及到需要通过HBase 列名进行数据过滤时可以考虑使用它。比较器细节及原理请参照之前的更文:

一。Java Api

头部代码

/** * 用于列名(Qualifier)过滤。 */ 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); // 造数据 myBase.putRows(connection, tableName, data); } Table table = connection.getTable(TableName.valueOf(tableName)); Scan scan = new Scan();

中部代码
向右滑动滚动条可查看输出结果。

1. BinaryComparator 构造过滤器 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] 2. BinaryPrefixComparator 构造过滤器 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] 3. SubstringComparator 构造过滤器 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] 4. RegexStringComparator 构造过滤器 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]

尾部代码

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(); } } 二。Shell Api 1. BinaryComparator 构造过滤器

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