SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '347397161a72bf5ee4c0b13c2573eaf537fcb1cb94c602d9c1b6f9164ef80a41' 
  AND token = 'GfX0K8/zDkQ9vYEyT6/flyYJH2GFx35ifSvuFgmMruw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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