Answer: tumbling

## Trigger Selection Analysis ### Requirements Analysis: - **Execution schedule**: Daily at 2 AM - **Critical requirement**: If the trigger stops and restarts, the next execution must occur at the next scheduled 2 AM time - **Key consideration**: Behavior after trigger restart ### Trigger Type Comparison: **A. Schedule Trigger** - **Pros**: Simple to configure for daily execution at specific times - **Cons**: Does NOT maintain state after restart; if stopped and restarted, it will execute immediately rather than waiting for the next scheduled time - **Restart behavior**: Executes immediately upon restart, potentially missing the intended 2 AM schedule **B. Tumbling Window Trigger** ✓ - **Pros**: - Maintains state and schedule integrity - If stopped and restarted, it resumes execution at the next scheduled window boundary - For daily execution, configure with 24-hour window size - Ensures exactly one execution per day at the specified time - **Restart behavior**: After restart, waits for the next 2 AM window rather than executing immediately **C. Storage Event Trigger** - **Not applicable**: Event-based trigger that responds to storage events, not scheduled execution **D. Custom Event Trigger** - **Not applicable**: Event-based trigger that responds to custom events, not scheduled execution ### Why Tumbling Window is Optimal: The tumbling window trigger's stateful nature ensures that after a restart, it calculates the next appropriate execution time based on the original schedule. This prevents immediate execution upon restart and maintains the intended daily 2 AM cadence. The trigger "remembers" its position in the execution sequence and resumes accordingly. ### Why Schedule Trigger is Less Suitable: While schedule triggers work well for simple recurring patterns, they lack the state persistence needed for the restart requirement. A restarted schedule trigger would execute immediately rather than waiting for the next 2 AM slot, potentially causing unwanted executions and disrupting the daily schedule. ### Configuration Recommendation: Configure the tumbling window trigger with: - Window size: 24 hours - Start time: 2 AM - Frequency: Daily - Max concurrency: 1 (to ensure only one instance runs at a time)

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