Hi Patrick,
LOAD statment have no option for this.
Your partition is by range/hash with Year on key?
Try if a selection by year load only the partition you want:
unload mseg;
select count(*) from (select * from mseg where mjahr='2012')
And check the resuls:
select schema_name,table_name,part_id,loaded from m_cs_tables where table_name = 'MSEG';
Regards, Fernando Da Rós