Case Statement in SSRS

In SQL Server Reporting Services (SSRS), the CASE statement is a powerful feature used to implement conditional logic within your reports. While SSRS itself doesn’t support the direct use of SQL’s CASE statement in expressions, you can achieve similar functionality using SSRS expressions and custom logic.

This blog will walk you through using case-like functionality in SSRS to create dynamic and flexible reports.

Table of Contents

• What is a CASE Statement?
  • Common Use Cases in SQL
• Difference between CASE Statement and SSRS Expressions
  • Why SSRS Doesn’t Directly Support CASE
  • SSRS Expression Syntax
• Implementing CASE Logic in SSRS
  • Using IIF Statements
  • Using SWITCH for Complex Conditions
• Examples of Conditional Logic in SSRS
  • Example 1: Conditional Formatting
  • Example 2: Dynamic Text Values
  • Example 3: Multi-condition Logic
• Best Practices for Conditional Logic in SSRS
• Conclusion
• FAQs

What is a CASE Statement?

A CASE statement in SQL allows a user to implement conditional logic in a query. This statement then assesses the query and returns the results based on the same.

Common Use Cases in SQL

• Mapping numeric values to descriptive text (e.g., 1 = “Active”).
• Implementing conditional aggregation.
• Handling null values with default values.

Why SSRS Doesn’t Directly Support the CASE Statement?

SSRS uses a different syntax for implementing conditional logic, relying on its built-in expression language instead of SQL’s CASE statement. This allows for greater flexibility in designing reports without requiring changes to the underlying SQL query.

SSRS expressions are written in Visual Basic .NET (VB.NET). You can use functions like IIF and SWITCH to replicate CASE statement logic in your reports.

Implementing CASE Logic in SSRS

1. Using IIF Statements

The IIF function is a simple way to add conditional logic.

Syntax:

=IIF(condition, true_result, false_result)

Example:

To display “High” if a value is greater than 100, and “Low” otherwise:

=IIF(Fields!Value.Value > 100, "High", "Low")

2. Using SWITCH for Complex Conditions

The SWITCH function is more suitable for multiple conditions.

Syntax:

=SWITCH(condition1, result1, condition2, result2, ..., True, default_result)

Example:

To categorize values into multiple ranges:

=SWITCH(  
    Fields!Value.Value < 50, "Low",  
    Fields!Value.Value >= 50 AND Fields!Value.Value <= 100, "Medium",  
    Fields!Value.Value > 100, "High"  
)

Examples of Conditional Logic in SSRS

Example 1: Conditional Formatting

Highlight a row in red if a value is negative.

1. Go to the Text Box Properties of the field you want to format.
2. Navigate to the Fill tab and set an expression for the background color:

=IIF(Fields!Value.Value < 0, "Red", "Transparent")

In the above example, if the Value  is negative, the background color of that row will be changed to red. Otherwise, it will remain transparent.

Example 2: Dynamic Text Values

Display a status based on a numeric value.

Expression for the text box:

=SWITCH( 

    Fields!StatusID.Value = 1, "Active", 

    Fields!StatusID.Value = 2, "Inactive", 

    True, "Unknown" 

)

In the above example, we have defined a condition where if the StatusID is 1, the status displayed will be “Active”. If the StatusID is 2, the status displayed will be “Inactive”. For any other value, the status displayed will be unkown.

Example 3: Multi-condition Logic

To calculate a discount based on order amount:

=SWITCH(  
    Fields!OrderAmount.Value < 100, "No Discount",  
    Fields!OrderAmount.Value >= 100 AND Fields!OrderAmount.Value < 500, "5% Discount",  
    Fields!OrderAmount.Value >= 500, "10% Discount"  
)

In the above example, we have declared a condition where if the Order Amount is less than 100, No Discount is applicable. If the Order amount value is greater than or equal to 100 but less than 500, a 5% discount will be applicable. At last, if the Order amount value is greater than and equal to 500, a 10% discount is allowed.

Best Practices for Conditional Logic in SSRS

• Use SWITCH for Readability: For multiple conditions, SWITCH is easier to read and maintain than nested IIF statements.
• Avoid Complex Expressions: Break down complex logic into calculated fields in your dataset if possible.
• Test Thoroughly: Verify your logic with test data to ensure all conditions are correctly handled.
• Keep Performance in Mind: Perform heavy calculations at the query level rather than in SSRS expressions.

Conclusion

While SSRS doesn’t directly support SQL’s CASE statement, you can use its built-in expressions, like IIF and SWITCH, to implement equivalent functionality. These tools provide powerful ways to apply conditional logic, allowing you to create dynamic and responsive reports. If you want to learn more about these techniques, then you should definitely check out the advanced SQL Course.

FAQs