hbase 过滤 - ITeye问答

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hbase 过滤0

目的：想做个分页查询。
思路：将条件封装成hbase filter.然后增加FirstKeyOnlyFilter.只获取first key 与分页参数比较，将第N的key分装成List<Get>,在去查询。

问题：
假设 family='s1' s1 列{"name","sex"}
    1.发现使用SingleColumnValueFilter，条件过滤查询时没问题。增加FirstKeyOnlyFilter后，当条件只包含name,或者sex时，则SingleColumnValueFilter条件没起作用。
    2.,将name,sex都用SingleColumnValueFilter封装成查询，在加上FirstKeyOnlyFilter,则可以查询出来。

简单代码
1.put
     ....
     List<Put> list=new ArrayList<Put>();
Put p = new Put("2".getBytes());
p.add("s2".getBytes(), "id".getBytes(), "222".getBytes());
p.add("s2".getBytes(), "name".getBytes(), "美女".getBytes());
p.add("s2".getBytes(), "sex".getBytes(), "女".getBytes());
list.add(p);
Put p2 = new Put("3".getBytes());
p2.add("s2".getBytes(), "id".getBytes(), "223".getBytes());
p2.add("s2".getBytes(), "name".getBytes(), "野兽".getBytes());
p2.add("s2".getBytes(), "sex".getBytes(), "男".getBytes());
list.add(p2);
htable.put(list);
htable.flushCommits();
   ....
2.select
   public static void selectByFilter(String tablename) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
FilterList filterList = new FilterList();
Scan s1 = new Scan(Bytes.toBytes("1"));
filterList.addFilter(new SingleColumnValueFilter("s2".getBytes(), "sex".getBytes(), CompareOp.EQUAL, "女".getBytes()));
// filterList.addFilter(new SingleColumnValueFilter("s2".getBytes(), "name".getBytes(), CompareOp.EQUAL, "美女".getBytes()));
filterList.addFilter(new FirstKeyOnlyFilter());
s1.setFilter(filterList);
ResultScanner ResultScannerFilterList = table.getScanner(s1);
for(Result rr=ResultScannerFilterList.next();rr!=null;rr=ResultScannerFilterList.next()){
for(KeyValue kv:rr.list()){
System.out.println(kv.getTimestamp()+":"+kv.getTotalColumnLength());
System.out.println("row : "+Long.parseLong(new String(kv.getBuffer(),kv.getRowOffset(),kv.getRowLength())));
System.out.println("column : "+new String(kv.getQualifier()));
System.out.println("value : "+new String(kv.getValue()));
}
}
table.close();
}
   将注释fileter打开则查询到2条，反之则是1条记录。
求教！！！

问题补充：select写错了。补充下。
FilterList filterList = new FilterList(Operator.MUST_PASS_ALL);