How to update columns in one table which will be referenced from another table column

Hi,

I have one requirement like below.I am using DB2 Z/OS 10 for this.


I have to update some flag values with some column values from one table
which will be referenced from another master table.


1) First i am fetching records from master table using condition.
2) Then updating few column values in child table with the master table data
3) Once values are updated into child table again i have to reset the column
values into master table with previous flag.

Currently i am using cursor logic to fetch first records from master table into variables.
Then updating the child table column by assigning the variable values.
Then again reseting the master table column values to the previous state.

By using cursor logic i am not able to update thousands of records in one time.

Can anyone please suggest some other logic to update child table records at a time.

Thanks in advance. :)