Hi Daniel,
This is a question long ago, but I suddenly come up with some more thoughts on
this. In a query as simple as this:
A = LOAD 'input';
B = FILTER A BY $1 == 1;
C = COGROUP A BY $0, B BY $0;
the optimizer will insert a split operator to reuse A. According to the source
code, a map
,
This is a question long ago, but I suddenly come up with some more thoughts
on
this. In a query as simple as this:
A = LOAD 'input';
B = FILTER A BY $1 == 1;
C = COGROUP A BY $0, B BY $0;
the optimizer will insert a split operator to reuse A. According to the
source
code, a map-reduce job
)
Daniel
Gang Luo wrote:
Hi all
according to the vldb 09 paper, the split operator and all its successive
operators reside in memory without any blocking in between. However, the source
code (version 0.7) shows that a MR job is actually ended when it meets the split
operator and multiple new MR jobs
Hi all
according to the vldb 09 paper, the split operator and all its successive
operators reside in memory without any blocking in between. However, the source
code (version 0.7) shows that a MR job is actually ended when it meets the
split
operator and multiple new MR jobs are created, each
