SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1eeec574b83d6e1e1ad8d609989526e95aeaa0eb53d74b473ceb08ef86a06c35' 
  AND token = 'j7H7RO+NUW3bHkxT0BKBbv0TLHYiNZFHpldhPZ/Bwto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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