localreport - Making rdlc datasource filter from other datasource -

so summarise problem, have report has 2 datasources - , 2 reports stuck each other. want second part of report display data based on first part of report showing.

to go more detail, situation follows. have 2 database tables - lets call 1 customers, , other orders.

customers contains data customers. orders contains link customers , contains person's orders.

the report supposed display sort of letter in part 1:

"hello [customername], have ongoing balance of [totalbalance] bla bla bla..." , list of orders has made in part 2 "order 1: item 1: 1 euro order 2: item 2: 2 euro ..."

originally these 2 separate reports generating 1 record @ time, outputting pdf files , merging them using third party software such letter , list of orders next each other. problem system need generate hundreds of them @ time, , taking ages. want pass pair of large data sources , generate them in batches (call them 600 @ time) - works faster.

so how can force second tablix uses different datasource, filter based on in first tablix own datasource?

i've looked @ subreports, work using reporting server , these local reports.

anything can ? i'm worried not possible.

there's no reason subreports won't work local reports.

i recommend download samples site reportviewer samples. project named "supplyingdata" shows how load data subreport.