SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4969be68d6fb706847c87c362245aec1a75d6cc2cf4f591714ff7c75c9c35d6c' 
  AND token = 'CUpbKDVLnYxwbSZjE++ZfGCYBXitXYsZn/J9NJ9HaHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00141

JSON explain

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