{"id":26130,"date":"2022-06-25T11:39:29","date_gmt":"2022-06-25T01:39:29","guid":{"rendered":"https:\/\/database.guide\/?p=26130"},"modified":"2022-06-27T11:57:39","modified_gmt":"2022-06-27T01:57:39","slug":"redis-expiretime-command-explained","status":"publish","type":"post","link":"https:\/\/database.guide\/redis-expiretime-command-explained\/","title":{"rendered":"Redis EXPIRETIME Command Explained"},"content":{"rendered":"\n

The Redis EXPIRETIME<\/code> command returns the absolute Unix timestamp in seconds at which the given key will expire. This is the number of seconds since 00:00:00 UTC on 1 January 1970 until the expiry time of the key.<\/p>\n\n\n\n

The EXPIRETIME<\/code> command was introduced in Redis 7.0.0.<\/p>\n\n\n\n\n\n\n\n

Syntax<\/h2>\n\n\n\n

The syntax goes like this:<\/p>\n\n\n\n

EXPIRETIME key<\/code><\/pre>\n\n\n\n
Where key<\/code> is the key for which to get the expiry time.<\/p>\n\n\n\n
Example<\/h2>\n\n\n\n
Suppose we set a key with an expiry:<\/p>\n\n\n\n
SET lunch \"Chicken Salad\" EX 86400<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
OK<\/pre>\n\n\n\n
We can now use the EXPIRETIME<\/code> command to check that key’s expiry time in Unix time:<\/p>\n\n\n\n
EXPIRETIME lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) 1655886492<\/pre>\n\n\n\n
This is the absolute Unix timestamp of the key’s expiry. If we run the statement again at a later time, we get exactly the same result:<\/p>\n\n\n\n
EXPIRETIME lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) 1655886492<\/pre>\n\n\n\n
The absolute Unix timestamp of the key’s expiry is not to be confused with the current time to live (TTL) of the key.<\/p>\n\n\n\n
Let’s run the TTL<\/code> command against it to check its TTL:<\/p>\n\n\n\n
TTL lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) 86214<\/pre>\n\n\n\n
We get an integer reply with the current time to live. If we run the same command again, we get a different result, due to the expiry getting nearer (and therefore, the time to live getting shorter):<\/p>\n\n\n\n
TTL lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) 86136<\/pre>\n\n\n\n
This is in contrast to the absolute Unix timestamp of the expiry.<\/p>\n\n\n\n
Keys Without an Expiry<\/h2>\n\n\n\n
If the key has no expiry, EXPIRETIME<\/code> returns an integer reply of -1<\/code>.<\/p>\n\n\n\n
To test this, let’s remove the expiry of our key:<\/p>\n\n\n\n
PERSIST lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) 1<\/pre>\n\n\n\n
The PERSIST<\/a><\/code> command removes any timeout on the given key. We got an integer reply of 1<\/code>, which means that it successfully removed the timeout on our key.<\/p>\n\n\n\n
Now let’s run EXPIRETIME<\/code> against that key:<\/p>\n\n\n\n
EXPIRETIME lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) -1<\/pre>\n\n\n\n
As expected, we get an integer reply of -1<\/code>, which means that the key doesn’t have an expiry set.<\/p>\n\n\n\n
Non-Existent Keys<\/h2>\n\n\n\n
If the key doesn’t exist, EXPIRETIME<\/code> returns an integer reply of -2<\/code>.<\/p>\n\n\n\n
Let’s delete our key: <\/p>\n\n\n\n
DEL lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) 1<\/pre>\n\n\n\n
The key has been deleted.<\/p>\n\n\n\n
And now let’s try to run EXPIRETIME<\/code> against the deleted key:<\/p>\n\n\n\n
EXPIRETIME lunch<\/code><\/pre>\n\n\n\n
Result:<\/p>\n\n\n\n
(integer) -2<\/pre>\n\n\n\n
As expected, an integer reply of -2<\/code>.<\/p>\n\n\n\n
There’s also a PEXPIRETIME<\/a><\/code> command that does the same thing as EXPIRETIME<\/code>, except that it returns the result in milliseconds.<\/p>\n","protected":false},"excerpt":{"rendered":"
The Redis EXPIRETIME command returns the absolute Unix timestamp in seconds at which the given key will expire. This is the number of seconds since 00:00:00 UTC on 1 January 1970 until the expiry time of the key. The EXPIRETIME command was introduced in Redis 7.0.0.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[153],"tags":[154,20],"class_list":["post-26130","post","type-post","status-publish","format-standard","hentry","category-redis","tag-commands","tag-what-is"],"_links":{"self":[{"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/posts\/26130","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/comments?post=26130"}],"version-history":[{"count":5,"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/posts\/26130\/revisions"}],"predecessor-version":[{"id":26265,"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/posts\/26130\/revisions\/26265"}],"wp:attachment":[{"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/media?parent=26130"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/categories?post=26130"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/database.guide\/wp-json\/wp\/v2\/tags?post=26130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}