Question

I am working with Spring batch. the batch will read several records each time from the database which look like this

personId |fromDate| toDate | someCode

*100 | 05-05-2011 | 31-12-2011 | A

*100 | 01-01-2012 | 31-12-2012 | A

100 | 01-01-2013 | 03-03-2013 | B

101 | 05-05-2011 | 31-12-2011 | A

*periodes to be merged.

What i want to do is to merge the periodes which has the same code and same personId, but not diffrent code or personId.

The first question is can i chunk this step? the problem is that commite intervals are static and i might not get all the priodes for a person in one chunk. is it possible to have dynamic chunks based on how many records for a person are on the table?

the next question is what is the best way to merge the periods? periods should be merged if the toDate is 31-12 and the next period starts from 01-01 of next year.

Answer 1

I solv the problem with using 2 pointer in each object. one which point to the previous period and one to the next period.
For chunking i needed to read all rows with same person id and aggregate them.