Writeback

Lumel EPM enables organizations to writeback and export planning data to multiple destination types, including file-based destinations, data warehouses, and data lake storage. It connects planning data with other data systems by making sure that updates to forecasts, scenario models, and user inputs can be easily saved to the backend data destinations and used again throughout the organization.

Unlike conventional BI and planning tools that require predefined database schemas and IT-managed writeback infrastructure, Lumel EPM eliminates the need for upfront database setup and static table definitions. Instead, it supports dynamic database configuration and runtime table creation, allowing writeback structures to be generated automatically based on planning context.

Lumel EPM performs semi-structured, on-the-fly writebacks, enabling data to be persisted in flexible formats without rigid schema constraints. Additionally, writeback operations can target multiple destinations simultaneously, ensuring consistency across files, warehouses, and data lakes without duplicating configuration effort.

1. Overview

To access writeback options and start writeback, click on the Writeback tab.

Writeback tab

It has the following sections:

Actions: This section has options to execute writeback and configure auto-writeback.

Destination: This section is about adding and managing writeback destinations.

Data: In this section, you can customize data-related options for writeback. For example, the 'Type' option allows you to specify how you want your data to be written back into the table - long, wide, and so on.

Logs - Every writeback event is logged with detailed information relevant to each writeback. Navigate to the writeback logs section to learn more.

Settings - Configure writeback-related settings. Navigate to the writeback settings section to learn more.

2. Add Destination

The first step before initiating writeback is to add one or more destinations where you can export your data table.

Add Destination

Lumel EPM supports quick writeback setup and execution for several types of data destinations. Configuring the writeback destination(s) is straightforward and involves a similar procedure for all destinations.

On-premise database servers need to be directly reachable from the internet for writeback. For this, on-premise servers must have a public IP address with port forwarding.

To learn how to configure each destination in the above list, navigate to this page.

The maximum number of rows that can be written back is 200k for Excel and CSV and 250 for OneDrive and SharePoint.

3. Steps to Writeback - Overview

Let us take an overview of the entire writeback workflow before going into the details in the following sections.

STEP 1: Navigate to the Writeback tab and then click on Add Destination.

Add Destination

STEP 2: Click on New Connection, and a list of destinations will be displayed for users to choose from.

Let's configure a OneDrive destination for demonstration purposes.

• Click on OneDrive and then click Next.

Select 'OneDrive'

• Configure the OneDrive destination by specifying the file path to which your writeback table will be saved, as well as the preferred file name.

File Path: Click on Browse to choose the required folder.

Writeback File Name: You can use the default file name or click Insert Variable to add a variable, such as date, time, or date and time, to your file name based on the time of writeback.

Setup Destination

• Click on Next. In the Configure Column window, you can adjust the number of decimal digits for values in the writeback columns. By default, numerical writeback columns support a 2-digit decimal precision.

Decimal Precision

• Click Finish. The OneDrive destination is successfully configured.

STEP 3: You can optionally walk through all of the writeback settings and make changes as required. Commonly used writeback options are available directly on the toolbar.

After configuring writeback settings, close the side panel.

STEP 4: Writeback. Click on Writeback to writeback your data table. A notification window will display the progress and status of the writeback.

Writeback

Your first writeback is now done successfully to the configured OneDrive destination. You can click on the highlighted link to view your written-back data. Click on the View log below if you wish to view the writeback logs.

Writeback done

The written-back file is shown below:

Writeback file in OneDrive

Note:

• After performing an initial writeback, you may need to add or remove visual parameters as you build your report. Any table structure changes required in the destination due to adding or removing visual parameters will be displayed in a notification window. You can choose whether to drop the existing table and recreate it with the new structure before writing back.

Writeback Table Mismatch Notification - Sample

• For some destinations, such as Snowflake, Lumel EPM automatically creates staging tables by default to writeback data in chunks when the number of rows being written back surpasses a threshold. If they are not configured automatically, you must enable a temporary staging table in the destination configuration in the admin console by clicking the link displayed. Writeback will not work unless the staging table option is enabled.

A sample error message for staging enablement

4. Writeback Settings - Optional

Lumel EPM empowers users to finely customize the writeback-related settings with just a few clicks. Basic settings are available on-the-go on the toolbar, while more options are available under General and Security settings. You can refer to the Settings section for more details.

4.1. Quick Writeback Settings

Writeback Type:

Choose the writeback type from the Type menu. You can choose how the data should be written back—Long, Wide, Long with Changes and Wide with Changes. These options are explained in detail under General settings.

Filter:

You can select specific data to writeback instead of writing back the entire table. These options are available under the Filter menu.

Column Rename:

Using this option, you can rename the writeback table columns.

Click on General to open the settings panel for writeback.

4.2. General Settings

In the general tab, set the writeback type, and optionally add filters and permissions. Learn more about General writeback options.

4.3. Data Settings

In the data tab, determine the scenarios and series to be written back and enable automatic writeback if applicable. Learn more about Data settings for writeback.

4.4. Destination Settings

Configure writeback destinations from the Destinations tab. Learn more about configuring destinations.

4.5. Advanced Settings

In the advanced tab, you can prevent writing back if a specific column that should not be empty contains null values. You can also rename native fields and specify a different column name to be written back. Learn more about advanced writeback settings.

5. Logs

Click the 'View Logs' button to navigate to the writeback log console and view details like the milestones, payload size, duration of the writeback, etc. Learn more about writeback logs.