DimensionStorage object not initialized with while select ?

hello..

i need to insert dimension segment (Description) in new field named dimension name

it's a new field in LedgerJournalTrans table

so in first

i put the code in modified method in LedgerJournalTrans.ledgerDimension in dataSource

the result is next 

and that what i need.

only problem the old transaction 

so i create new job to update all transaction

can anyone help ?

thank you in advance.