问题
I have 2 load statements in a pig script as below:
a=load 'file1.dat' using HCatLoader();
b=load 'file2.dat' using HcatLoader();
After these, I have some transformations on a and b seperately. If we run this pig script in batch mode, does the load and transformations of both files happen sequentially or in parallel? I was thinking that pig optimises this script and runs both the loads in parallel. But not 100% sure. Can anyone comment on this?
回答1:
Each load command will run in parallel, but the commands in pig script will run serial.
来源：https://stackoverflow.com/questions/34052356/load-operations-in-pig-script-sequential-or-parallel