Convert Power M query to snowflake view

DineshArivu  what I understood from you PQ code that you are spliting SERVICEPERIOD into Service Period From/To dates, but later discards them.

You filters rows to only those where SCHEDULEID contains "MRR" and builds a key MergeWID_InvoiceDate = CUSTOMERID + invoice month-year (from INVOICECREATEDDATE, formatted MMM-yy).

Then you removes the duplicates and groups by that key and creates 2 lists seperated by a comma : 1st InsertedCreatedDate the group invoice dates and 2nd InvoiceCreatedBy the list of distinct creators.

This is how I imagine the query : 

create or replace view DATALAKE.DM_BSS_OSS.VW_MRR_INVOICE_CREATED as
with base as (
  select
      CUSTOMERID,
      cast(INVOICECREATEDDATE as date) as INVOICECREATEDDATE,
      INVOICECREATEDBY,
      SCHEDULEID
  from DATALAKE.DM_BSS_OSS.VW_WD_INVOICE_WITHPRODUCTHIERARCHY
  where SCHEDULEID ilike '%MRR%'
),
dedup as (  
  select distinct
      (CUSTOMERID || to_char(INVOICECREATEDDATE, 'Mon-YY')) as MERGEWID_INVOICEDATE,
      INVOICECREATEDDATE,
      INVOICECREATEDBY
  from base
)
select
    MERGEWID_INVOICEDATE,
    listagg(to_char(INVOICECREATEDDATE, 'Mon-DD-YYYY'), ',')
      within group (order by INVOICECREATEDDATE asc) as INSERTEDCREATEDDATE,
    listagg(distinct trim(INVOICECREATEDBY), ', ') as INVOICECREATEDBY
from dedup
group by MERGEWID_INVOICEDATE