hive select count(*) 报错,帮忙看看 3C

select count(*) from db_hive.student;
WARNING: Hive-on-MR is deprecated in Hive 2 and may not be available in the future versions. Consider using a different execution engine (i.e. tez, spark) or using Hive 1.X releases.
Query ID = root_20171012025616_0d673cbd-6c2b-421b-bffc-98e2c4d8d676
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=
In order to limit the maximum number of reducers:
set hive.exec.reducers.max=
In order to set a constant number of reducers:
set mapreduce.job.reduces=
Starting Job = job_1507801793754_0002, Tracking URL = http://192.168.163.130:8088/proxy/application_1507801793754_0002/
Kill Command = /usr/hadoop/bin/hadoop job -kill job_1507801793754_0002
Hadoop job information for Stage-1: number of mappers: 1; number of reducers: 1
2017-10-12 02:56:29,615 Stage-1 map = 0%, reduce = 0%
2017-10-12 02:56:36,331 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.15 sec
2017-10-12 02:56:42,700 Stage-1 map = 100%, reduce = 100%, Cumulative CPU 2.64 sec
MapReduce Total cumulative CPU time: 2 seconds 640 msec
java.io.IOException: java.lang.OutOfMemoryError: PermGen space
at org.apache.hadoop.mapred.ClientServiceDelegate.invoke(ClientServiceDelegate.java:338)
at org.apache.hadoop.mapred.ClientServiceDelegate.getTaskCompletionEvents(ClientServiceDelegate.java:390)
at org.apache.hadoop.mapred.YARNRunner.getTaskCompletionEvents(YARNRunner.java:583)
at org.apache.hadoop.mapreduce.Job$5.run(Job.java:680)
at org.apache.hadoop.mapreduce.Job$5.run(Job.java:677)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692)
at org.apache.hadoop.mapreduce.Job.getTaskCompletionEvents(Job.java:677)
at org.apache.hadoop.mapred.JobClient$NetworkedJob.getTaskCompletionEvents(JobClient.java:349)
at org.apache.hadoop.hive.ql.exec.mr.HadoopJobExecHelper.computeReducerTimeStatsPerJob(HadoopJobExecHelper.java:612)
at org.apache.hadoop.hive.ql.exec.mr.HadoopJobExecHelper.progress(HadoopJobExecHelper.java:570)
at org.apache.hadoop.hive.ql.exec.mr.ExecDriver.execute(ExecDriver.java:424)
at org.apache.hadoop.hive.ql.exec.mr.MapRedTask.execute(MapRedTask.java:151)
at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:199)
at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:100)
at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:2182)
at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:1838)
at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1525)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1236)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1226)
at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:233)
at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:184)
at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:403)
at org.apache.hadoop.hive.cli.CliDriver.executeDriver(CliDriver.java:821)
at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:759)
at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:686)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Caused by: java.lang.OutOfMemoryError: PermGen space
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2625)
at java.lang.Class.getMethod0(Class.java:2866)
at java.lang.Class.getMethod(Class.java:1676)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.getReturnProtoType(ProtobufRpcEngine.java:293)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:258)
at com.sun.proxy.$Proxy72.getTaskAttemptCompletionEvents(Unknown Source)
at org.apache.hadoop.mapreduce.v2.api.impl.pb.client.MRClientProtocolPBClientImpl.getTaskAttemptCompletionEvents(MRClientProtocolPBClientImpl.java:177)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.mapred.ClientServiceDelegate.invoke(ClientServiceDelegate.java:324)
at org.apache.hadoop.mapred.ClientServiceDelegate.getTaskCompletionEvents(ClientServiceDelegate.java:390)
at org.apache.hadoop.mapred.YARNRunner.getTaskCompletionEvents(YARNRunner.java:583)
at org.apache.hadoop.mapreduce.Job$5.run(Job.java:680)
at org.apache.hadoop.mapreduce.Job$5.run(Job.java:677)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692)
Ended Job = job_1507801793754_0002 with exception 'java.io.IOException(java.lang.OutOfMemoryError: PermGen space)'
FAILED: Hive Internal Error: java.lang.OutOfMemoryError(PermGen space)
java.lang.OutOfMemoryError: PermGen space

MapReduce Jobs Launched:
Stage-Stage-1: Map: 1 Reduce: 1 Cumulative CPU: 2.64 sec HDFS Read: 7728 HDFS Write: 101 SUCCESS
Total MapReduce CPU Time Spent: 2 seconds 640 msec
AsyncLogger error handling event seq=105, value='[ERROR calling class org.apache.logging.log4j.core.async.RingBufferLogEvent.toString(): java.lang.NullPointerException]':
java.lang.OutOfMemoryError: PermGen space
Exception in thread "main" java.lang.OutOfMemoryError: PermGen space

0

2个回答

在hive中暂不支持select count(_*) from table这种写法, 可以改写成select count(1) from table ,效果一样

0

hive在版本0.6后已经加入了对count( * )支持的patch,很明显题主的语句并没有报编译的错误。
根据提供的信息:FAILED: Hive Internal Error: java.lang.OutOfMemoryError(PermGen space)
java.lang.OutOfMemoryError: PermGen space
应该是内存泄漏的问题。
可以从下面几点找一下问题:
1. 给每个进程JVM分配的内存大小是否过小
2. 是否在跑这个查询的同时,还有其他命令在执行
3. 是否这个表真的过大

0
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最近看到某公司面试题有这个,顺便查了一下。count(*):所有行进行统计,包括NULL行count(1):所有行进行统计,包括NULL行count(column):对column中非Null进行统计我在集群找了一个表试了一下,结果差距不是很大,因为执行时间会受集群资源的影响,所以看下具体的执行步骤先看结果,count(*)执行时间26sselect count(*) from ods.baseo...
关于SELECT COUNT(*)的问题....
Adodc1.RecordSource = "SELECT COUNT(lhd1.ID) FROM lhd1"rnrn我怎么样才能把ID个数的值给一个变量?rnrnAdodc1.RecordSource = "SELECT COUNT(lhd1.ID) FROM lhd1 where ID between " & 80 & " and " & 90 & ""rn这样能知道ID号为80与90之间 有多少个IDrn我想一次就能得到0~10, 11~20,.... 91~100 这10个区间的值,该怎么做?
要用多少次select count(*)?
统计符合某一条件的记录总数rnselect count(*) from table where city='北京'rnselect count(*) from table where city='上海'rnrn如果城市有100个,我要统计每个城市的记录数量,rn难道要select count(*) 100次?rn1000个呐?1000次?rnrn有点晕了...rn
oracle select count(*) 很慢
oracle select count(*) 很慢 表中大楷有1千万条数据 我想得到 记录数 有没有好的方法优化 请赐教
select , count ,group by ????
表A: id,name,nickrn表B: news_id,name,title,bodyrnA为用户表,B为信息表rn需要的结果:查出每个用户在B表中对应的信息条数
select count(*) as DLTimes ....
在c#中,这个语句怎样写啊,主要是count(*)部分rn请详细一些rn谢谢
mysql: select count until?
我想查询一个id按顺序wait_order排序后,count前面有多少个。rnmysql 有until这样的语句吗?rnselect count(*) from reserves order wait_order until id = 3;rnrn`reserves` (rn `id` int(11) NOT NULL AUTO_INCREMENT,rn `member_id` int(11) NOT NULL DEFAULT '0',rn `wait_order` smallint(4) NOT NULL DEFAULT '0'rnrnid, member_id, wait_orderrn1, 3, 1rn2, 3, 3rn3, 1, 2rn4, 2, 4rnrnrn
关于select的count问题
strSQL = ""rn strSQL = strSQL & "SELECT SEIKEIKI_CODE,MIN(OUT_TIME) AS MIN_TIME, "rn strSQL = strSQL & "MAX(OUT_TIME) AS MAX_TIME, "rn strSQL = strSQL & "WORKER_NAME,SHIFT,COUNT(NAME) AS NAME "rn strSQL = strSQL & "FROM D_LOTDATA "rn strSQL = strSQL & "WHERE APP_FLAG = 0 AND NAME = 'HONSU' "rn strSQL = strSQL & "GROUP BY WORKER_NAME,SHIFT,OUT_DATE "rnrn想要在记录集里统计NAME = 'HONSU'的数目,因为NAME也可以不等于'HONSU',所以上面的语句缩小了 MIN(OUT_TIME) AS MIN_TIME的范围,rn请问我如何在不缩小MIN(OUT_TIME) AS MIN_TIME的范围的同时,统计rnNAME = 'HONSU'的数目?
Select Count(*)的解决
我原先在数据库的过程中使用了:rn SELECT COUNT (*)rn INTO icountnumberrn FROM Recordmasterrn WHERE (reckoningdate >= istartdate AND reckoningdate < ienddate)rn AND (datatype = '01')rn但是当数据量越来越大的时候,使用rnCOUNT (*)就不行了,全表扫描太受不了了;rn如果在程序中,我可以用Query控件的Count来得到记录的行数,但是在Oracle的过程里怎么写才能得到icountnumber值,不用SELECT COUNT (*)的方式?
关于Select count 请教
例rnSelect Shop_ProductsName,count(*) as sss from Tx_Shop group by Shop_ProductsNamern这一句正常rn但要可以查询 Tx_Shop表中的其他字段Shop_Pmoney,所有我这样写rnSelect Shop_ProductsName,count(*) as sss,Shop_Pmoney from Tx_Shop group by Shop_ProductsNamern但不能执行rnrn请教大侠们,在线等。。。
select count(*) from tb
[Quote=引用 2 楼 dobear_0922 的回复:]rn不可能表扫描,使用索引的优先顺序:非聚集索引>聚集索引>堆索引rn[/Quote]rnrn这种不带条件的统计,因为不需要扫描数据行,只需要扫描索引页的页头(就像下面的 m_slotCnt = 6 表示这一页有6条数据),所以索引页越少,速度越快,rnrn[code=SQL]PAGE HEADER:rnrnrnPage @0x072B0000rnrnm_pageId = (1:769) m_headerVersion = 1 m_type = 1rnm_typeFlagBits = 0x4 m_level = 0 m_flagBits = 0x0rnm_objId (AllocUnitId.idObj) = 1341 m_indexId (AllocUnitId.idInd) = 256 rnMetadata: AllocUnitId = 72057594125811712 rnMetadata: PartitionId = 72057594080526336 Metadata: IndexId = 1rnMetadata: ObjectId = 545437017 m_prevPage = (0:0) m_nextPage = (0:0)rnpminlen = 8 m_slotCnt = 6 m_freeCnt = 7908rnm_freeData = 272 m_reservedCnt = 0 m_lsn = (10393:1231:2)rnm_xactReserved = 0 m_xdesId = (0:0) m_ghostRecCnt = 0rnm_tornBits = 0 [/code] rnrnrn[Quote=引用 6 楼 dobear_0922 的回复:]rnrn非聚集索引的页数一般比聚集索引的少很多,可以提高效率的。rn[/Quote]rn
关于select count(*) 的问题!
比如表结构和数据如下:rnrnid typeid namernrn1 2 arnrn2 2 b rnrn3 3 crnrn4 3 drnrnrn我想实现 select count(*) as nums 。。。 where typeid=2 以及每一条记录的name,即所有的记录都出现,如下形式:rnrnnums namern2 arn2 brnrnrn请问如何写 sql ? mysql5.0 以上版本
Hive查询count(*)有数据,但是select * 没有数据
若发生将一个使用LZO压缩过的表数据导入一个没有被压缩过表内, 类似于如下两个表: 图一:LZO压缩 图二未压缩 查询将出现这种状况,hdfs目录下明明有数据,count(*)有数据总量,但是select就是查询不出来, 具体原因: 表的结构是未压缩过的,但是数据是压缩过的,通过select(此处查询的方法跟表的结构有关系)查询压缩过的结果,肯定不会显示, 具体解决办法: 使用se...
hive 执行 select count(*) from table 无法返回结果?
我部署了一个节点的hadoop(2.6.0)伪分布式系统,然后部署了hive,启动了hadoop和hive之后,通过命令rn# hive --service cli 进入hive的客户端,rnrn然后执行一个查询 show tables;rnrnhive_focusrnrn显示有这个表,然后我执行 select * from hive_tables;rnrn可以查出数据rnrn但是,当我执行 select count(1) from hive_tables;之后,查询一直停留在这里rn[img=https://img-bbs.csdn.net/upload/201601/11/1452496630_410105.png][/img]rn我只有一个节点,一条数据,按理说不可能一直不往下执行啊,求各位大神指点一下,刚研究hadoop,不太明白,谢谢各位!
Select Count(b.topic)
SQL代码rnrnselect u.sex,u.individualism,count(b.tpoic),u.Points,u.Experience,u.Charm,u.VisiteTimes,u.LastDate,rn u.regdate,u.Imgpath,u.Uemail,u.QQID,u.Individualsignature from Users as u inner join BulletinList as b rn on(u.userid=b.userid) and u.userName='超级管理员'GROUP BY u.userid,b.userid rnrn报错“u.Sex' 在选择列表中无效,因为该列既不包含在聚合函数中,也不包含在 GROUP BY 子句中。”rnrn请问要怎么获得count(b.tpoic)发表文章的次数!rn谢谢啊!
SELECT COUNT(*) FROM $table_members
SELECT COUNT(*) FROM $table_membersrnrn上面这句话中的count(*)是什么意思?
关于select count (*)的问题
运行时提示“未找到预期from关键字”rn with query1 dorn beginrn sql.clear;rn sql.add('select count (*) as number from E_BASIC where ecode='''+edit1.text+'''');rn open;rn if fieldbyname('number').asinteger >0 thenrn showmessage('right');rn end;
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