DATE_DIFF()

Measuring Durations Response Time Analysis This query calculates response time in minutes and categorizes performance. Sub-hour granularity is critical for support SLAs where 15 minutes versus 45 minutes makes a significant difference. Aggregating Durations This query calculates session statistics per user: how many sessions, average duration, and total time spent. These metrics are fundamental for user engagement analysis. What unit should you measure in for different use cases? DATE_DIFF() Uses Time difference calculations power some of the most important operational metrics in industry. For SLA calculations where every minute matters, measure in seconds and divide for display. Measuring directly in hours can misclassify a 59-minute ticket as a 0-hour resolution.

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