Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a83adc517935afe5014722f2acb6284d2cd0703397adc4cd7a5a9a330e30b18' 
  AND token = '6ovB49typsjs9ifGZHQcj3Huf6ldCH5yOfpMdiGWSQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}