Chapter-6: Creating a Drill Down Report in SSRS
Drilldown/Tree view report is actually a group by report but displaying only the summary at first instance and we can see the further detail on clicking + sign on grouped column as shown below.
Download Full Tutorial for Chapter-6-Creating-a-DrillDownReport-in-SSRS
Download BasicSSRS1 SSRS Drilldown Report Sample Project

So in Chapter-6 we are going to design Drilldown report as shown above. It is very simple to design using SSRS. The steps to do so are
Step 1: Open the SSRS Reporting Project of Chapter-5 with shared data source and create a tabular report with following query on Northwind database with country as first column.
select Country,CompanyName,ContactName,Address from Customers order by Country

Step2: Add Parent Group for country field as shown

Step 3: From the Tablix Group window, let us choose [Country] from Group By DropDown and check Add Group Header checkbox and click OK.

The report will look like as under

And running the report will yield the following result.

Step 4: From Row groups, choose [Country] Details and then choose Group Properties.

Step 5: From the Group Properties window that opens up, choose Visibility tab. Then select Hide radio button and check the Display can be toggled by this report item checkbox. Then from the drop down that will be enable, select the name of the group which is country1 and click on OK button.

Step 6: Delete the country column from the report design.

Step-7: Report is successfully developed now run the report you will see the following output as.

Chapter-1: Creating a basic Tabular SSRS Report using Report Wizard
Chapter-2 : Report Deployment on SQL Server 2012 Reporting Server
Chapter-3:Opening/Calling the deployed SQL Server Reporting Server report from Asp.net
Chapter-4 Creating SSRS Matrix Report / Cross Tab Report
Chapter-5 Creating a Sub Report in SSRS
Chapter-6: Creating a Drill Down Report in SSRS
Chapter-7: Working with expressions and custom code in SSRS
Chapter-8-SSRS (Reporting Services) Working with Calculated fields
Chapter-9-Sorting of Column and Custom Paging in SSRS
Chapter-10 : Creating and Deploying Web Services for SSRS
Chapter-11 : Creating SSRS Report by consuming Web Service Data Source
Chapter-12 : Working with Data Bars in SSRS
Chapter-13-Displaying Color in Data Bar Based on Condition
Chapter-14- Displaying Data Labels along with Data Bars in SSRS
Chapter-15-Displaying Indicators in SSRS
Chapter-16-Creating SSRS Linked Report
Chapter-17 Adding or Creating Drop Down Parameter List in SSRS
Chapter-18 Creating Group above or stepped report in SSRS
Chapter-19-Creating Multi Value Parameter Report in SSRS
Chapter-20-Using CSS Stylesheet in SSRS