SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b24830c4a2ffbc8ddf688188ecbab4885133b1bb32745133ffab1745db9c7b7e' 
  AND token = '5fig6cztnwV3KbkCI5hoj/DzPe2TNRAq0crwUZzt+SI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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