Check if a record exists without iterating

Most developers instinctively call next() when checking if records exist, which forces ServiceNow to hydrate the entire GlideRecord object with field data you'll never use. The hasNext() method only checks if results exist without loading field values, making it significantly faster for existence checks. The real trap is forgetting setLimit(1) — without it, ServiceNow still prepares the entire result set even though you only care about existence.

When to use this pattern

• Business Rules that need to validate related record existence before processing
• Script Includes performing duplicate detection or conflict checking
• Scheduled Jobs that need to skip processing when prerequisite records don't exist
• Fix Scripts checking data integrity before bulk operations

When NOT to use this pattern

• Don't use in Client Scripts — use GlideAjax with a Script Include instead
• Don't use when you need a count — use GlideAggregate with addAggregate('COUNT')
• Don't use inside a loop over another GlideRecord — you'll create N+1 query performance problems
• Don't use when you actually need field values — just use next() and process the data

Key behaviors and gotchas

• Always call setLimit(1) — without it, the database still processes the full result set
• hasNext() respects ACLs and will return false if records exist but the user can't read them
• State values in queries must be integers: addQuery('state', '1') not addQuery('state', 'New')
• Query performance depends heavily on indexed fields — always include indexed fields in your addQuery() conditions
• Domain separation affects results — records in different domains may not be visible