SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0075c9e6baf2a33b82f858705e6fda387dd981f2b6a5efa8b24a874b847e67c8' 
  AND token = 'XfLCKIcEiI7yyhsRxVDxAJfqGH4hOxZox9hEKb5E5+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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