zoukankan html css js c++ java

HBase编程 API入门系列之delete.deleteColumn和delete.deleteColumns区别（客户端而言）（4）

　　心得，写在前面的话，也许，中间会要多次执行，连接超时，多试试就好了。

　　delete.deleteColumn和delete.deleteColumns区别是：

　　　　deleteColumn是删除某一个列簇里的最新时间戳版本。

　　　　delete.deleteColumns是删除某个列簇里的所有时间戳版本。

hbase(main):020:0> desc 'test_table'
Table test_table is ENABLED
test_table
COLUMN FAMILIES DESCRIPTION
{NAME => 'f', DATA_BLOCK_ENCODING => 'NONE', BLOOMFILTER => 'ROW', REPLICATION_SCOPE => '0', VERSIONS => '1', COMPRESSION => 'NONE', MIN_VERSIONS => '0', TTL => 'FOREVER', KEEP_DELETED_CELLS
=> 'FALSE', BLOCKSIZE => '65536', IN_MEMORY => 'false', BLOCKCACHE => 'true'}
1 row(s) in 0.2190 seconds

hbase(main):021:0> scan 'test_table'
ROW COLUMN+CELL
row_01 column=f:col, timestamp=1478102698687, value=maizi
row_01 column=f:name, timestamp=1478104345828, value=Andy
row_02 column=f:name, timestamp=1478104477628, value=Andy2
row_03 column=f:name, timestamp=1478104823358, value=Andy3
3 row(s) in 0.2270 seconds

hbase(main):022:0> scan 'test_table'
ROW COLUMN+CELL
row_01 column=f:col, timestamp=1478102698687, value=maizi
row_01 column=f:name, timestamp=1478104345828, value=Andy
row_02 column=f:name, timestamp=1478104477628, value=Andy2
row_03 column=f:name, timestamp=1478104823358, value=Andy3
3 row(s) in 0.1480 seconds

hbase(main):023:0> scan 'test_table',{VERSIONS=>3}
ROW COLUMN+CELL
row_01 column=f:col, timestamp=1478102698687, value=maizi
row_01 column=f:name, timestamp=1478104345828, value=Andy
row_02 column=f:name, timestamp=1478104477628, value=Andy2
row_03 column=f:name, timestamp=1478104823358, value=Andy3
3 row(s) in 0.1670 seconds

hbase(main):024:0>

 1 package zhouls.bigdata.HbaseProject.Test1;
 2 
 3 import javax.xml.transform.Result;
 4 
 5 import org.apache.hadoop.conf.Configuration;
 6 import org.apache.hadoop.hbase.HBaseConfiguration;
 7 import org.apache.hadoop.hbase.TableName;
 8 import org.apache.hadoop.hbase.client.Delete;
 9 import org.apache.hadoop.hbase.client.Get;
10 import org.apache.hadoop.hbase.client.HTable;
11 import org.apache.hadoop.hbase.client.Put;
12 import org.apache.hadoop.hbase.util.Bytes;
13 
14 public class HBaseTest {
15     public static void main(String[] args) throws Exception {
16         HTable table = new HTable(getConfig(),TableName.valueOf("test_table"));//表名是test_table
17         Put put = new Put(Bytes.toBytes("row_04"));//行键是row_04
18         put.add(Bytes.toBytes("f"),Bytes.toBytes("name"),Bytes.toBytes("Andy0"));//列簇是f，列修饰符是name，值是Andy0
19 //        put.add(Bytes.toBytes("f2"),Bytes.toBytes("name"),Bytes.toBytes("Andy3"));//列簇是f2，列修饰符是name，值是Andy3
20         table.put(put);
21         table.close();
22 
23 //        Get get = new Get(Bytes.toBytes("row_04"));
24 //        get.addColumn(Bytes.toBytes("f1"), Bytes.toBytes("age"));如现在这样，不指定，默认把所有的全拿出来
25 //        org.apache.hadoop.hbase.client.Result rest = table.get(get);
26 //        System.out.println(rest.toString());
27 //        table.close();
28 
29 //        Delete delete = new Delete(Bytes.toBytes("row_2"));
30 //        delete.deleteColumn(Bytes.toBytes("f1"), Bytes.toBytes("email"));
31 //        delete.deleteColumn(Bytes.toBytes("f1"), Bytes.toBytes("name"));
32 //        table.delete(delete);
33 //        table.close();
34 
35 
36 //        Delete delete = new Delete(Bytes.toBytes("row_03"));
37 //        delete.deleteColumn(Bytes.toBytes("f"), Bytes.toBytes("name"));
38 //        delete.deleteColumns(Bytes.toBytes("f"), Bytes.toBytes("name"));
39 //        table.delete(delete);
40 //        table.close();
41 }
42 
43     public static Configuration getConfig(){
44         Configuration configuration = new Configuration(); 
45 //        conf.set("hbase.rootdir","hdfs：HadoopMaster:9000/hbase");
46         configuration.set("hbase.zookeeper.quorum", "HadoopMaster:2181,HadoopSlave1:2181,HadoopSlave2:2181");
47         return configuration;
48     }
49 }

hbase(main):038:0> scan 'test_table'
ROW COLUMN+CELL
row_01 column=f:col, timestamp=1478102698687, value=maizi
row_01 column=f:name, timestamp=1478104345828, value=Andy
row_02 column=f:name, timestamp=1478104477628, value=Andy2
row_03 column=f:name, timestamp=1478123664884, value=Andy3
3 row(s) in 0.1910 seconds

hbase(main):039:0> scan 'test_table'
ROW COLUMN+CELL
row_01 column=f:col, timestamp=1478102698687, value=maizi
row_01 column=f:name, timestamp=1478104345828, value=Andy
row_02 column=f:name, timestamp=1478104477628, value=Andy2
row_03 column=f:name, timestamp=1478123664884, value=Andy3
row_04 column=f:name, timestamp=1478123917775, value=Andy0
4 row(s) in 0.1310 seconds

delete.deleteColumn和delete.deleteColumns区别是：

　　　　deleteColumn是删除某一个列簇里的最新时间戳版本。

　　　　delete.deleteColumns是删除某个列簇里的所有时间戳版本。

 1 package zhouls.bigdata.HbaseProject.Test1;
 2 
 3 import javax.xml.transform.Result;
 4 
 5 import org.apache.hadoop.conf.Configuration;
 6 import org.apache.hadoop.hbase.HBaseConfiguration;
 7 import org.apache.hadoop.hbase.TableName;
 8 import org.apache.hadoop.hbase.client.Delete;
 9 import org.apache.hadoop.hbase.client.Get;
10 import org.apache.hadoop.hbase.client.HTable;
11 import org.apache.hadoop.hbase.client.Put;
12 import org.apache.hadoop.hbase.util.Bytes;
13 
14 public class HBaseTest {
15     public static void main(String[] args) throws Exception {
16         HTable table = new HTable(getConfig(),TableName.valueOf("test_table"));//表名是test_table
17         Put put = new Put(Bytes.toBytes("row_04"));//行键是row_04
18         put.add(Bytes.toBytes("f"),Bytes.toBytes("name"),Bytes.toBytes("Andy1"));//列簇是f，列修饰符是name，值是Andy0
19 //        put.add(Bytes.toBytes("f2"),Bytes.toBytes("name"),Bytes.toBytes("Andy3"));//列簇是f2，列修饰符是name，值是Andy3
20         table.put(put);
21         table.close();
22 
23 //        Get get = new Get(Bytes.toBytes("row_04"));
24 //        get.addColumn(Bytes.toBytes("f1"), Bytes.toBytes("age"));如现在这样，不指定，默认把所有的全拿出来
25 //        org.apache.hadoop.hbase.client.Result rest = table.get(get);
26 //        System.out.println(rest.toString());
27 //        table.close();
28 
29 //        Delete delete = new Delete(Bytes.toBytes("row_2"));
30 //        delete.deleteColumn(Bytes.toBytes("f1"), Bytes.toBytes("email"));
31 //        delete.deleteColumn(Bytes.toBytes("f1"), Bytes.toBytes("name"));
32 //        table.delete(delete);
33 //        table.close();
34 
35 
36 //        Delete delete = new Delete(Bytes.toBytes("row_03"));
37 //        delete.deleteColumn(Bytes.toBytes("f"), Bytes.toBytes("name"));
38 //        delete.deleteColumns(Bytes.toBytes("f"), Bytes.toBytes("name"));
39 //        table.delete(delete);
40 //        table.close();
41 }
42 
43     public static Configuration getConfig(){
44         Configuration configuration = new Configuration(); 
45 //        conf.set("hbase.rootdir","hdfs：HadoopMaster:9000/hbase");
46         configuration.set("hbase.zookeeper.quorum", "HadoopMaster:2181,HadoopSlave1:2181,HadoopSlave2:2181");
47         return configuration;
48     }
49 }

delete.deleteColumn和delete.deleteColumns区别是：

　　　　deleteColumn是删除某一个列簇里的最新时间戳版本。

　　　　delete.deleteColumns是删除某个列簇里的所有时间戳版本。

查看全文

相关阅读:
HackerRank savita-and-friends
HackerRank training-the-army
51Nod 1378 夹克老爷的愤怒
 51Nod 1380 夹克老爷的逢三抽一
 Codeforces 566 D. Restructuring Company
BZOJ 2822: [AHOI2012]树屋阶梯
 Codeforces Gym 101138 G. LCM-er
51Nod 1250 排列与交换
 BZOJ 1511: [POI2006]OKR-Periods of Words
BZOJ 1355: [Baltic2009]Radio Transmission

原文地址：https://www.cnblogs.com/zlslch/p/6156265.html