SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd83a38edcec0fba1b67d804aa7cc9f11d092bf5b4b4bf0ae8214ca7e9980ad1' 
  AND token = 'gFKnfmY4zveHaScgLzHLklyigGbkmxhugXiIZt2UTWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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