Can you give an example? Please also include the results of "explain <query>" so we can see how many map-reduce jobs are there.
Zheng On Fri, Jun 5, 2009 at 1:21 AM, Min Zhou <[email protected]> wrote: > but is there any way to define row format of files outputed by command > "INSERT OVERWRITE LOCAL DIRECTORY '/tmp/aaa' SELECT ..." ? If I create an > external table to store result , then put it to local by that command, more > mapred job needed. > > Min > > > On Fri, Jun 5, 2009 at 2:04 PM, Zheng Shao <[email protected]> wrote: > >> Use dfs -getmerge. >> >> By the way, if you just want text file format, "INSERT OVERWRITE LOCAL >> DIRECTORY '/tmp/aaa' SELECT ..." is good enough. You don't need to split the >> process into 2 steps. >> >> Zheng >> >> >> On Thu, Jun 4, 2009 at 8:22 PM, Min Zhou <[email protected]> wrote: >> >>> So how do you copy them back? >>> use dfs -germerge or INSERT OVERWRITE LOCAL DIRECTORY? >>> >>> Thanks, >>> Min >>> >>> >>> On Thu, Jun 4, 2009 at 1:48 PM, Zheng Shao <[email protected]> wrote: >>> >>>> No, we would need to copy the file back from HDFS. But I think there is >>>> no overhead - we are doing the same thing as INSERT OVERWRITE LOCAL >>>> DIRECTORY, I think. >>>> >>>> Zheng >>>> >>>> >>>> On Wed, Jun 3, 2009 at 10:45 PM, Min Zhou <[email protected]> wrote: >>>> >>>>> Can external table stored at a local directory? >>>>> >>>>> >>>>> On Thu, Jun 4, 2009 at 1:42 PM, Zheng Shao <[email protected]> wrote: >>>>> >>>>>> You can first create an external table and then insert into that >>>>>> table. >>>>>> >>>>>> Zheng >>>>>> >>>>>> >>>>>> On Wed, Jun 3, 2009 at 10:31 PM, Min Zhou <[email protected]>wrote: >>>>>> >>>>>>> Hi all, >>>>>>> >>>>>>> Any helps? >>>>>>> >>>>>>> >>>>>>> thanks, >>>>>>> Min >>>>>>> -- >>>>>>> My research interests are distributed systems, parallel computing and >>>>>>> bytecode based virtual machine. >>>>>>> >>>>>>> My profile: >>>>>>> http://www.linkedin.com/in/coderplay >>>>>>> My blog: >>>>>>> http://coderplay.javaeye.com >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Yours, >>>>>> Zheng >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> My research interests are distributed systems, parallel computing and >>>>> bytecode based virtual machine. >>>>> >>>>> My profile: >>>>> http://www.linkedin.com/in/coderplay >>>>> My blog: >>>>> http://coderplay.javaeye.com >>>>> >>>> >>>> >>>> >>>> -- >>>> Yours, >>>> Zheng >>>> >>> >>> >>> >>> -- >>> My research interests are distributed systems, parallel computing and >>> bytecode based virtual machine. >>> >>> My profile: >>> http://www.linkedin.com/in/coderplay >>> My blog: >>> http://coderplay.javaeye.com >>> >> >> >> >> -- >> Yours, >> Zheng >> > > > > -- > My research interests are distributed systems, parallel computing and > bytecode based virtual machine. > > My profile: > http://www.linkedin.com/in/coderplay > My blog: > http://coderplay.javaeye.com > -- Yours, Zheng
