SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f895b9bb1407fe2d2f58e94ef92b441182b6fb9c45c43ca829ad8b4692847e8' 
  AND token = 'RbKTf5+s0IvfC9mHin8vAkzOSEdLPyP8jhk4ZhQojXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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