dgcov on "Storing arrays in post_meta"

When I ask for a post's meta value, it comes as an array or a string.

Can I store an array of values?

For example, if I have an array $postIDs=array(21,47,81,32), can I store it with update_post_meta($post_id, 'postIDs', $postIDs)?

Currently, I'm joining the array into a string and storing that.

$postIDstring = implode(",", $postIDs);
update_post_meta($post_id, 'postIDs', $postIDstring);

Then I'm extracting it:$postIDstrings=update_post_meta($post_id, 'postIDs');

$postIDs=explode(",",$postIDstrings[0]);

How does it work?

- - , .
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