This can be done with AQL where function. Check out our documentation (we have listed your use case as a sample usage as well ): where | Holistics Docs
Specifically, you can create a semi-additive AQL metric that only gets the value of the last day. The metric expression would look something like this:
measure | where(date = max(date))
For example, you want to get the count of orders created in the last day of each month:
measure total_value_monthly {
name: 'Total Value Monthly'
type: 'number'
definition: @aql Value
| count(Value.Value)
| where(Value.Date == max(Value.Date))
}