SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2266deab7c261d278759cae5d4c9f45a922bf9a6e1ef45350ea339db05198f53' 
  AND token = 'RYmle5jpNqK/rC0LxUdcwvr5NrW/QTQUmthJFgl6ZL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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