Implementing error handling and logging within SSRS

 Implementing error handling and logging in SQL Server Reporting Services (SSRS) involves several approaches since SSRS itself does not provide built-in comprehensive error handling or logging mechanisms. Here are some strategies to handle errors and implement logging in SSRS:

1. Using Try-Catch in SQL Queries:

   • Within your SQL queries, use TRY-CATCH blocks to handle exceptions. You can log errors to a table in your database.

   sql
   BEGIN TRY
       -- Your SQL code here
   END TRY
   BEGIN CATCH
       INSERT INTO ErrorLog (ErrorMessage, ErrorSeverity, ErrorState, ErrorLine, ErrorProcedure)
       VALUES (ERROR_MESSAGE(), ERROR_SEVERITY(), ERROR_STATE(), ERROR_LINE(), ERROR_PROCEDURE());
       -- You can also raise the error again if needed
       THROW;
   END CATCH;

2. Custom Code in SSRS Reports:

   • You can write custom code in SSRS reports (using VB.NET) to handle certain errors and log them. Go to the Report Properties and add your custom code under the 'Code' tab.

   vb
   Public Function LogError(ByVal errorMsg As String) As String
       ' Write your custom error logging logic here
       ' For example, write to a file or a database table
       Return errorMsg
   End Function
   

   • Call this function in your report expressions to handle and log errors.

3. SSRS Event Handlers:

   • Use SSRS event handlers in the Report Server to capture and log errors. This involves creating custom extensions or using Report Server event handlers.

4. Using Report Server Execution Logs:

   • SSRS includes execution logs that can be used to monitor and troubleshoot report execution. These logs include information about report execution times, parameters, and errors.
   • Configure and query the ReportServer database’s ExecutionLog3 view to analyze report executions and errors.

   sql
   SELECT *
   FROM ReportServer.dbo.ExecutionLog3
   WHERE Status = 'rsProcessingAborted' OR Status = 'rsRuntimeError'

5. Custom Logging Tables:

   • Create custom logging tables in your database to log report parameters, execution times, and errors manually.

   sql
   CREATE TABLE ReportExecutionLog (
       ReportName NVARCHAR(255),
       ExecutionTime DATETIME,
       Parameters NVARCHAR(MAX),
       ErrorMessage NVARCHAR(MAX),
       Status NVARCHAR(50)
   );
   

   • Insert logs into this table at appropriate places in your reports or stored procedures.

   sql
   INSERT INTO ReportExecutionLog (ReportName, ExecutionTime, Parameters, ErrorMessage, Status)
   VALUES (@ReportName, GETDATE(), @Parameters, @ErrorMessage, @Status);

6. Configuring Report Server Logging Options:

   • Configure the SSRS Report Server to log more detailed information by modifying the RSReportServer.config file. Increase the logging level to capture more detailed information.

   xml
   <Configuration>
       <LogLevel>Verbose</LogLevel>
   </Configuration>

7. Using Subscriptions and Notifications:

   • Set up report subscriptions to send notifications when a report execution fails. This can help in proactive error handling.

By combining these techniques, you can create a robust error handling and logging mechanism for your SSRS reports. Each approach has its specific use cases and can be tailored to meet the needs of your reporting environment.

Advanced Parameter Handling in SSRS

 Advanced parameter handling in SQL Server Reporting Services (SSRS) can greatly enhance the flexibility and functionality of your reports. Here are some advanced techniques and best practices:

1. Cascading Parameters

Cascading parameters are parameters that depend on the value of another parameter. This is useful for creating dynamic filters.

Example: Country and City Parameters

1. Create Country Parameter:

   • Dataset Query: SELECT DISTINCT Country FROM YourTable ORDER BY Country

2. Create City Parameter:

   • Dataset Query:

     sql
     
     SELECT DISTINCT City 
     FROM YourTable 
     WHERE Country = @Country 
     ORDER BY City
     

2. Multi-Value Parameters

Multi-value parameters allow users to select multiple values from a list. These are useful for filtering reports based on multiple criteria.

Example: Using Multi-Value Parameters in Query

1. Create a multi-value parameter (e.g., @Regions).
2. Modify the dataset query to handle multiple values:

   sql
   
   SELECT * 
   FROM YourTable 
   WHERE Region IN (@Regions)
   

3. Dynamic SQL in SSRS

Using dynamic SQL can help handle complex filtering logic based on parameter values.

Example: Dynamic Filtering Based on Parameter

1. Define a parameter (e.g., @FilterBy).
2. Use dynamic SQL in the dataset query:

   sql
   
   DECLARE @SQL NVARCHAR(MAX)
   SET @SQL = 'SELECT * FROM YourTable WHERE 1=1'
   
   IF @FilterBy = 'Option1'
       SET @SQL = @SQL + ' AND Column1 = ''Value1'''
   ELSE IF @FilterBy = 'Option2'
       SET @SQL = @SQL + ' AND Column2 = ''Value2'''
   
   EXEC sp_executesql @SQL
   

4. Default and Null Values

Handling default and null values for parameters ensures your report behaves correctly when users do not provide input.

Example: Default Value for Date Parameter

1. Define a date parameter (e.g., @StartDate).
2. Set the default value to today’s date:

   sql
   
   =IIF(Parameters!StartDate.Value Is Nothing, Today(), Parameters!StartDate.Value)
   

5. Parameter Dependencies and Conditional Visibility

Control the visibility of parameters and report elements based on parameter values.

Example: Conditional Visibility

1. Define a parameter (e.g., @ShowDetails).
2. Set the visibility of a report item based on the parameter:

   vb
   
   =IIF(Parameters!ShowDetails.Value = "Yes", False, True)
   

6. Using Lookup Functions

Lookup functions allow you to retrieve values from different datasets based on parameter values.

Example: Using Lookup to Display Related Data

1. Define datasets (e.g., Dataset1 and Dataset2).
2. Use Lookup to display related data in the report:

   vb
   
   =Lookup(Fields!ID.Value, Fields!ID.Value, Fields!Description.Value, "Dataset2")
   

7. Custom Code for Advanced Logic

You can add custom code to your report for complex parameter handling and transformations.

Example: Custom Code for Date Formatting

1. Add custom code to the report:

   vb
   
   Public Function FormatDate(ByVal dateValue As DateTime) As String
       Return dateValue.ToString("MMMM dd, yyyy")
   End Function
   

2. Use the custom code in an expression:

   vb
   
   =Code.FormatDate(Fields!DateField.Value)
   

8. Handling Large Parameter Lists

For reports with large parameter lists, consider using cascading parameters, filters, or creating a separate dataset to load parameter values on demand.

Example: Filter Parameter List

1. Create a main dataset (e.g., MainDataset).
2. Create a parameter dataset with a filter:

   sql
   
   SELECT DISTINCT Value 
   FROM ParameterTable 
   WHERE Condition = @Condition
   

By using these advanced parameter handling techniques in SSRS, you can create more dynamic, user-friendly, and efficient reports.