Documentation

Error Detection

Real-time validation and error detection to catch issues before script execution.

Types of Errors Detected

Syntax Errors
Invalid Qlik script syntax
  • • Missing semicolons
  • • Unmatched parentheses/brackets
  • • Invalid function calls
  • • Malformed LOAD statements
  • • Incorrect JOIN syntax
Logic Errors
Logical issues in script flow
  • • Undefined field references
  • • Circular table dependencies
  • • Unreachable code blocks
  • • Variable scope issues
  • • Data type mismatches
Performance Issues
Code that may impact performance
  • • Inefficient JOIN operations
  • • Missing WHERE clauses
  • • Redundant calculations
  • • Large Cartesian products
  • • Memory-intensive operations
How Real-time Validation Works
Understanding the error detection process

As You Type

Errors are detected immediately as you type, with visual indicators appearing directly in the editor. Red underlines show syntax errors, while yellow highlights indicate potential issues.

Context Analysis

The analyzer understands your script context, tracking table definitions, field names, and variable declarations to provide accurate error detection and suggestions.

Live Error Detection Example
LOAD 
  CustomerID,
  CustomerName,
  Date#(OrderDate, 'YYYY-MM-DD') as OrderDate
FROM DataSource
WHERE CustomerID > 0
  AND OrderDate >= '2023-01-01'  // ❌ Error: OrderDate not yet defined
  AND InvalidField IS NOT NULL;  // ❌ Error: InvalidField doesn't exist

LEFT JOIN (Customers)  // ⚠️ Warning: Table 'Customers' not defined above
LOAD 
  CustomerID
  OrderAmount,  // ❌ Error: Missing comma on previous line
  Count(*)      // ❌ Error: Aggregate without GROUP BY
FROM Orders;    // ❌ Error: Missing WHERE clause for large table
Performance Impact
Understanding the performance implications of error detection

✅ Lightweight

Error detection runs efficiently in the background without impacting typing performance or editor responsiveness.

⚡ Debounced

Validation is debounced to avoid excessive processing while you're actively typing and editing code.

🎯 Configurable

You can adjust validation frequency and disable specific error types for optimal performance on your system.