Filters and Stored Procedure

You can use the 'filters' input in the configurations to configure it. Here is the documentation about the same - docs.appian.com/.../Export_To_Excel_Smart_Service.html

so , will it be like a!queryFilter(now()-1) for getting last months data .If the process runs once on start of each month

a!localVariables(
  local!endOfMonth: eomonth(now(), 0),
  local!splittedDate: split(local!endOfMonth, "/"),
  local!endDateWithTime: datetime(
    local!splittedDate[3],
    local!splittedDate[1],
    local!splittedDate[2],
    "23",
    "59",
    "59",
    "59"
  ),
  a!queryLogicalExpression(
    operator: "AND",
    filters: {
      a!queryFilter(
        field: "createdOn_dtm",
        operator: "<",
        value: local!endDateWithTime
      ),
      a!queryFilter(
        field: "createdOn_dtm",
        operator: ">",
        value: datetime(year(now()), month(now()), 1, 00, 00, 00, 00)
      )
    }
  )
)

Thanks ,but i  could not understand properly .

As the documentation suggests, I have added a logical expression here which allows assigning multiple filters at once. So I have added 2 filters. One for checking that the date in the DB should be greater than the first date of this month and also less than the last date of the same month. 

How can i create a stored procedure to delete data from DB for last month for 2 tables.

You have to create the stored procedure into DB and use that stored procedure in Appian by using Execute stored procedure function/Smart Service. Alternate Way is you can use delete from data store entity to delete the data from DB. for this initially, you can fetch the primary keys of the particular entity by using the filter and queryEntity and use those primary key variable in identifier config of the same Smart service or function(delete from datastore entity). Other than that, you can use query database smartservice as well to delete the data from DB based on conditions.