LWCIntermediatewirecachingperformance
Implement client-side filter on wired data without re-fetching Apex
Real World Scenario
LWC wires cacheable Apex returning 2000 products then client filters by category. Re-filter re-fetches Apex unnecessarily.
Expected Answer
• Store wire result in module or @track masterList reference
• Client filter derives displayedList from masterList on category change
• Re-fetch only when user clicks Refresh or record context changes
• Debounce text filter on client array for substring search
• Warn user when client filter dataset exceeds performance threshold
• Server filter for initial load reducing payload if 2000 is too many
• Jest test filter does not increment Apex mock call count
Follow-Up Questions & Answers
Click to expand — each follow-up includes a direct, interview-ready answer
Main difference: use case and scale. Store wire result in module or @track masterList reference. Client filter derives displayedList from masterList on category change. Pick based on your integration pattern and team capability. Wire once filter many is correct for medium datasets—know when to push filter to server. Balance speed of delivery with maintainability.
Architect Perspective
Wire once filter many is correct for medium datasets—know when to push filter to server.