Hey there, For databases, there needs to be a way to actually infer boundaries for a particular column. Simply performing a "select *" would not be enough because we would not know how to query the database.
-Abe On Mon, Sep 8, 2014 at 8:33 PM, [email protected] < [email protected]> wrote: > Hi,all. > In sqoop we can specify the parameter --split-by,which can determine > which field we will use to split map recored. > But if the split field's data is skew.The workload between maps will be > imbalance.I > want to know why sqoop does not use > select count(*) from table/num-maps to determine each map's workload.As I > know some other base class of DataDrivenDBInputFormat's > has the implementation of select count(*) from table/num-maps.Then why > sqoop override this. > > >
