Oracle Fast Formulas - Chapter 21: Error Handling in Oracle Fast Formulas

 

Chapter 21: Error Handling in Oracle Fast Formulas

Overview

Error handling is a crucial part of Oracle Fast Formula development. Effective error handling ensures that formulas fail gracefully and help identify issues during processing. This chapter explains how to handle errors and implement best practices to make debugging and maintenance easier.

---

Key Concepts

1. Formula Compilation Errors
   These occur when there is a syntax mistake or invalid logic in the formula. These are typically caught at the time of formula saving or validation.

2. Runtime Errors
   These happen when a formula executes and encounters unexpected data or logic conditions (e.g., divide by zero).

3. Return Values
   Use RETURN statements wisely to manage flow. If an error is likely, plan default returns.

---

Common Techniques for Error Handling

1. Use of IF Conditions

plsql
IF input_value IS NULL THEN
   RETURN 'DEFAULT_VALUE'
ELSE
   RETURN input_value

2. Avoiding Divide by Zero

plsql
IF divisor != 0 THEN
   result = dividend / divisor
ELSE
   result = 0

3. Log Messages with Default Values

Oracle doesn’t offer print statements, but structured logic and audit tools help track issues.

---

Example: Handle Missing Inputs

plsql
INPUTS ARE hours_worked, hourly_rate

IF hours_worked IS NULL THEN
   hours_worked = 0
ENDIF

IF hourly_rate IS NULL THEN
   hourly_rate = 0
ENDIF

total_pay = hours_worked * hourly_rate

RETURN total_pay

---

Best Practices

• Always check inputs before processing.

• Avoid hard stops or assumptions about available data.

• Return default values that make sense for your business rules.

• Document assumptions and fallback mechanisms clearly in comments.

• Use formula result rules to track issues at the payroll level.

---

Practice Quiz

1. What happens if you do not check for NULL values in your formula?

   • a) Formula returns default

   • b) Formula throws runtime error ✅

   • c) Nothing changes

   • d) Compiler automatically corrects it

2. Which construct helps avoid divide-by-zero?

   • a) WHILE loop

   • b) RETURN statement

   • c) IF condition ✅

   • d) DEFAULT formula