SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd9c4290c85f97e63572f5884786b843639cac4e5facf366743f94481176707e7' 
  AND token = 'Mgdzx2ketgBXm0qLQPkrfmRKfwgz7BVdD8uLEnVUXCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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