Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dda06e665b1b9cd0d0bdbaca7f73fb19dfd86031f09f4127e3bbe2cc4f44b2b' 
  AND token = 'Rv7l5LSRroBgTMC7PTAmZKO/XHvV5rpKDQ5FQyMtm7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}