


Calculating Time Differences in MySql: Using DATEDIFF for Day Precision
When working with timestamps in MySql, it is often necessary to determine the time difference between two values. While simple subtraction may suffice in certain scenarios, obtaining an accurate difference in days requires a specific approach.
If the time portion is not relevant in the calculation, DATEDIFF() is the recommended function for determining the number of days between two timestamps. It directly computes the difference and returns it as a simple numeric value:
<code class="sql">SELECT DATEDIFF('2010-10-08 18:23:13', '2010-09-21 21:40:36') AS days;</code>
This query will return 17, since the difference between the two dates is 17 full days. Notably, the time components are ignored in this calculation.
Therefore, to accurately obtain the difference between two timestamps in days, converting the timestamps to a datetime format and using DATEDIFF() provides the most precise and efficient solution.
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