hbase中filter查询例子

最新推荐文章于 2022-05-17 16:27:42 发布

qwert9016

最新推荐文章于 2022-05-17 16:27:42 发布

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http://blog.youkuaiyun.com/karen_wang/archive/2011/03/28/6284154.aspx

1、需要的jar包：

commons-codec-1.4.jar

commons-logging-1.0.4.jar

hadoop-0.20.2-core.jar

hbase-0.20.6.jar

log4j-1.2.15.jar

zookeeper-3.2.2.jar

2、已有表结构：

1、表名：scores

2、列族：

course:art

course:math

grade:

3、scan 'scores'的内容：

ROW                          COLUMN+CELL
Jerry                       column=course:art, timestamp=1301294630194, value=80
Jerry                       column=course:math, timestamp=1301294630132, value=100
Jerry                       column=grade:, timestamp=1301294630073, value=2
Jim                         column=course:art, timestamp=1301294630363, value=97
Jim                         column=course:math, timestamp=1301294630305, value=100
Jim                         column=grade:, timestamp=1301294630247, value=3
Tom                         column=course:art, timestamp=1301294630015, value=97
Tom                         column=course:math, timestamp=1301294629987, value=87
Tom                         column=grade:, timestamp=1301294629931, value=1

4、代码：

package org.myhbase;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.filter.FilterList;
import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
import org.apache.hadoop.hbase.filter.CompareFilter.CompareOp;
import org.apache.hadoop.hbase.io.Cell;
import org.apache.hadoop.hbase.util.Bytes;
public class HBaseBasic03 {
private static HBaseConfiguration hbaseConfig=null;
static{
Configuration config=new Configuration();
config.set("hbase.zookeeper.quorum","192.168.10.149,192.168.10.44,192.168.10.49");
config.set("hbase.zookeeper.property.clientPort", "2181");
hbaseConfig=new HBaseConfiguration(config);
}
public static void selectByRowKey(String tablename,String rowKey) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
Get g = new Get(Bytes.toBytes(rowKey));
Result r=table.get(g);
for(KeyValue kv:r.raw()){
System.out.println("column: "+new String(kv.getColumn()));
System.out.println("value: "+new String(kv.getValue()));
}
}
public static void selectByRowKeyColumn(String tablename,String rowKey,String column) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
Get g = new Get(Bytes.toBytes(rowKey));
g.addColumn(Bytes.toBytes(column));
Result r=table.get(g);
for(KeyValue kv:r.raw()){
System.out.println("column: "+new String(kv.getColumn()));
System.out.println("value: "+new String(kv.getValue()));
}
}
//通过表中的值来查询
public static void selectByFilter(String tablename,List<String> arr) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
FilterList filterList = new FilterList();
Scan s1 = new Scan();
for(String v:arr){ // 各个条件之间是“与”的关系
String [] s=v.split(",");
filterList.addFilter(new SingleColumnValueFilter(Bytes.toBytes(s[0]),
Bytes.toBytes(s[1]),
CompareOp.EQUAL,Bytes.toBytes(s[2])
)
);
// 添加下面这一行后，则只返回指定的cell，同一行中的其他cell不返回
// s1.addColumn(Bytes.toBytes(s[0]), Bytes.toBytes(s[1]));
}
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("row : "+new String(kv.getRow()));
System.out.println("column : "+new String(kv.getColumn()));
System.out.println("value : "+new String(kv.getValue()));
}
}
}
public static void main(String [] args) throws IOException{
// 按rowkey查询，查询Tom行的所有cell
HBaseBasic03.selectByRowKey("scores","Tom");
// 按rokey 和 column 来查询，查询Tom行course列族的所有列值
HBaseBasic03.selectByRowKeyColumn("scores","Tom","course");
// Filter多条件查询，条件：查询 course列族中art列值为97 ，且 course列族中math列值为100的行
List<String> arr=new ArrayList<String>();
arr.add("course,art,97");
arr.add("course,math,100");
HBaseBasic03.selectByFilter("scores",arr);
}
}