The last update time in Redis is often required when it comes to synchronization or cache invalidation. This information can help in understanding when a key-value pair was last modified and hence, whether the data is stale or not.
Please note that Redis itself does not provide direct commands to fetch the last update time of a key. However, we can maintain this information ourselves within our Python code. Here is how you might do this:
Example 1: Manual tracking of last update time
In this example, every time a key is set, another key with the same name appended by
_last_updated is also set with the current timestamp. To get the last updated time, simply fetch this key.
Does Redis provide a built-in feature for this? No, Redis does not have a built-in feature to get the last update time of a key. It needs to be manually tracked.
What happens when setting a non-existent timestamp key? If you try to retrieve a non-existent timestamp key, Redis will return None.