为了模拟场景,需要一张全量表,和一张增量表,由于数据源有限,所以两个表都来自Oracle中的OMP_SERVICE,全量表包含所有数据,在Hive中名称叫service_all,增量表包含部分时间段数据,在Hive中名称叫service_tmp。
hive> show tables;
OK
searchlog
searchlog_tmp
service_all
service_tmp
Time taken: 0.04 seconds, Fetched: 4 row(s)
hive> select count(*) from service_all;
Total jobs = 1
Launching Job 1 out of 1
Number of reduce tasks determined at compile time: 1
In order to change the average load for a reducer (in bytes):
set hive.exec.reducers.bytes.per.reducer=<number>
In order to limit the maximum number of reducers:
set hive.exec.reducers.max=<number>
In order to set a constant number of reducers:
set mapreduce.job.reduces=<number>
Starting Job = job_1407233914535_0013, Tracking URL = http://FBI003:8088/proxy/application_1407233914535_0013/
Kill Command = /home/fulong/Hadoop/hadoop-2.2.0/bin/hadoop job -kill job_1407233914535_0013
Hadoop job information for Stage-1: number of mappers: 3; number of reducers: 1
2014-08-21 16:51:47,389 Stage-1 map = 0%, reduce = 0%
2014-08-21 16:51:59,816 Stage-1 map = 33%, reduce = 0%, Cumulative CPU 1.36 sec
2014-08-21 16:52:01,996 Stage-1 map = 67%, reduce = 0%, Cumulative CPU 2.45 sec
2014-08-21 16:52:07,877 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 3.96 sec
2014-08-21 16:52:17,639 Stage-1 map = 100%, reduce = 100%, Cumulative CPU 5.29 sec
MapReduce Total cumulative CPU time: 5 seconds 290 msec
Ended Job = job_1407233914535_0013
MapReduce Jobs Launched:
Job 0: Map: 3 Reduce: 1 Cumulative CPU: 5.46 sec HDFS Read: 687141 HDFS Write: 5 SUCCESS
Total MapReduce CPU Time Spent: 5 seconds 460 msec
OK
6803
Time taken: 59.386 seconds, Fetched: 1 row(s)
hive> select count(*) from service_tmp;
Total jobs = 1
Launching Job 1 out of 1
Number of reduce tasks determined at compile time: 1
In order to change the average load for a reducer (in bytes):
set hive.exec.reducers.bytes.per.reducer=<number>
In order to limit the maximum number of reducers:
set hive.exec.reducers.max=<number>
In order to set a constant number of reducers:
set mapreduce.job.reduces=<number>
Starting Job = job_1407233914535_0014, Tracking URL = http://FBI003:8088/proxy/application_1407233914535_0014/
Kill Command = /home/fulong/Hadoop/hadoop-2.2.0/bin/hadoop job -kill job_1407233914535_0014
Hadoop job information for Stage-1: number of mappers: 3; number of reducers: 1
2014-08-21 16:53:03,951 Stage-1 map = 0%, reduce = 0%
2014-08-21 16:53:15,189 Stage-1 map = 67%, reduce = 0%, Cumulative CPU 2.17 sec
2014-08-21 16:53:16,236 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 3.38 sec
2014-08-21 16:53:57,935 Stage-1 map = 100%, reduce = 22%, Cumulative CPU 3.78 sec
2014-08-21 16:54:01,811 Stage-1 map = 100%, reduce = 100%, Cumulative CPU 5.34 sec
MapReduce Total cumulative CPU time: 5 seconds 340 msec
Ended Job = job_1407233914535_0014
MapReduce Jobs Launched:
Job 0: Map: 3 Reduce: 1 Cumulative CPU: 5.66 sec HDFS Read: 4720 HDFS Write: 3 SUCCESS
Total MapReduce CPU Time Spent: 5 seconds 660 msec
OK
13
Time taken: 75.856 seconds, Fetched: 1 row(s)