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name: Wheels Debugging description: Troubleshoot common Wheels errors and provide debugging guidance. Use when encountering errors, exceptions, or unexpected behavior. Provides error analysis, common solutions, and debugging strategies for Wheels applications.

Wheels Debugging

Common Errors

"Missing argument name" Error

Cause: Mixed positional and named arguments

Solution: Use consistent argument style

Copy❌ hasMany("comments", dependent="delete")
✅ hasMany(name="comments", dependent="delete")

"Can't cast Object type [Query] to [Array]"

Cause: Using Array functions on queries

Solution: Use query methods

Copy❌ ArrayLen(post.comments())
✅ post.comments().recordCount

"Association not found" Error

Cause: Association not properly defined or typo

Solution:

1. Check model config() for association definition
2. Verify association name matches
3. Check model name spelling

"Table not found" Error

Cause: Migration not run or table name mismatch

Solution:

Copywheels dbmigrate latest

"Column not found" Error

Cause: Property doesn't exist in database

Solution:

1. Add column via migration
2. Check property name spelling
3. Verify case sensitivity

Debugging Tools

Enable Debug Output

Copy// In config/settings.cfm
set(showDebugInformation=true);
set(showErrorInformation=true);

Inspect Variables

Copy<cfdump var="#post#" label="Post Object">
<cfabort>

Check SQL Queries

Copy// Wheels logs all SQL to debugging output
// Look for red SQL queries (errors)

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Generated by: Wheels Debugging Skill v1.0