SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c41098cb4a5c90fe0a7b5a77bc39c1b17307dd46c64389cd02fa20190c4e4b19' 
  AND token = 'T1aUZk1lmiQD3zM33Op2bMoyL4+khjF94L9ok54Qls0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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