Why Are My MySQL Queries Returning Empty Results When Searching for Dates Older Than a Specific Time?

Querying for Datetimes Older Than a Specified Time

In a database management system like MySQL, you may encounter situations where you need to retrieve records that match a specific time range. One common scenario is retrieving data that is older than a particular time.

In MySQL, you can leverage the DATE_SUB() function in combination with the WHERE clause to achieve this. The following query exemplifies this approach:

<code class="sql">WHERE creation_date < DATE_SUB(NOW(), INTERVAL 15 MINUTE)

This query will retrieve all records from the creation_date column where the datetime value is older than 15 minutes from the current time.

Correcting an Issue

However, if you are experiencing an issue where the above query returns empty results despite having records that meet the criteria, you may need to reverse the inequality symbol < to >. The corrected query should look like this:

<code class="sql">WHERE creation_date > DATE_SUB(NOW(), INTERVAL 15 MINUTE)</code>

This will specify that you want to retrieve records where the datetime value is older than 15 minutes from the current time.

By using the correct inequality symbol, you can ensure that your query accurately retrieves the desired records within the specified time range.

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