SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '628fa80ca4e596e0038b72cd75cb5744ea57de0e29c595a82ce7e5de075c6cc3' 
  AND token = 'i03wf2yap1UoDsvcytS8ZMRBtQUiyDC+aGCTplHxm2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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