SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dec528fb572f40d90ebfff057fbc532fa1b14cec2325aa9a4824bb98a4b687b2' 
  AND token = 'Fq69TQzmnkQhEutUsVP1XOmuE9AH/noMgPwxF4ahxZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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