How to implement DatesYTD and DatesMTD using LookML

[salehaxsid]

Implementation of DatesYTD, DatesMTD using LookML is simple, you just have to create another explore with sql_where condition of existing view that has transaction date. 
For Example:

We have a view "Orders" and it has transaction dates as Order_Date and there is "orderdetails" view which is the fact table.
The Model file will have something like:
 explore: orders{ }

explore:orderdetails{
join : order{

type: lef t outer

sql_on: orderdetails.orderid=orders.orderid

relationship: many to one

}}

Add a date filter in fact table orderdetails.view:
filter: DateFilter{

type: date

}
Now we will add DatesYTD explore in Model file:

explore: DatesYtd{

view_name:orders

}
Join this DatesYTD with Order details:
explore: Orderdetails{

join: datesytd{
     type: left_outer
     sql_on: ${orderdetails.order_id}= ${datesytd.orderid};; 

--[OrderID is primary key and orderdetails have expansion of order view]

     relationship: many_to_one
     sql_where: ${datesytd.orderdate}>=cast (Date_trunc({% date_start datefilter %}, year) as timestamp) and
    ${datesytd.orderdate}<=cast(LAST_DAY(cast (Date_trunc({% date_start datefilter %}, month) as date))as timestamp) ;;

--[logic to derive the value from DateFilter using liquid variable reference and compare it with OrderDate to filter Data according to YTD format]
}}

Now apply the Sql_where condition on orders explore where it is being joined by orderdetails as well so that the transaction dates present in orders get filtered by the date filter we created in orderdetail:

sql_where: {% condition datefilter %} ${orders.orderdate} {% endcondition %}

So now you can use the Date column present in  DatesYTD explore to filter out data according to YTD and also to filter the transaction dates in Orders view.

In dashboard we will be using the filter we created in orderdetails view. Whenever user selects a date in DateFilter, it is being used by DatesYTD explore and Orders explore to filter dates in a way that selected month date is made as last date of that month and first date will be 1st Jan of the year selected in filter.

With this method you can use normal dates for normal filtering of Data and DatesYTD for YTD format filtering too, also you can implement the same workaround for DatesMTD by changing the condition in sql_where clause.