> ## Documentation Index
> Fetch the complete documentation index at: https://learn.nextedy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Data Mapping Parameters

> Nextedy GANTT data mapping parameters define how Polarion work item fields are mapped to Gantt scheduling properties.

export const LastReviewed = ({date}) => {
  if (!date) return null;
  const formatted = new Date(`${date}T00:00:00Z`).toLocaleDateString("en-US", {
    year: "numeric",
    month: "long",
    day: "numeric",
    timeZone: "UTC"
  });
  return <p className="mt-10 text-sm text-gray-400 dark:text-zinc-500 not-prose">
      Last reviewed on {formatted}
    </p>;
};

## Field Mapping Parameters

| Parameter            | Type   | Default           | Supported Field Types  | Description                                                                                         |
| -------------------- | ------ | ----------------- | ---------------------- | --------------------------------------------------------------------------------------------------- |
| `Start Field`        | String | `gantt_start`     | Date, DateTime, String | Work item field storing the task start date.                                                        |
| `End Field`          | String | None              | Date, DateTime, String | Work item field storing the task end date.                                                          |
| `Duration Field`     | String | `gantt_duration`  | Integer, String        | Work item field storing the task duration in days (or hours in high-precision mode).                |
| `Progress Field`     | String | `gantt_progress`  | Float, String          | Work item field storing the task progress as a float value from 0.0 (0%) to 1.0 (100%).             |
| `Duration Precision` | Enum   | `Standard (Days)` | N/A                    | Controls whether durations are tracked in days or hours. Values: `Standard (Days)`, `High (Hours)`. |

## Valid Field Combinations

You must configure at least two of the three date-related fields. The Gantt calculates the missing field from the other two.

| Combination      | Start Field | End Field | Duration Field | Behavior                                  |
| ---------------- | ----------- | --------- | -------------- | ----------------------------------------- |
| Start + Duration | Required    | Not set   | Required       | End date calculated from start + duration |
| Start + End      | Required    | Required  | Not set        | Duration calculated from date range       |
| End + Duration   | Not set     | Required  | Required       | Start date calculated from end - duration |

<Frame>
  <img src="https://mintcdn.com/none-17b4493f/umKaPvHwUHw-ZQFM/gantt/diagrams/reference/widget-parameters/data-mapping/diagram-1.svg?fit=max&auto=format&n=umKaPvHwUHw-ZQFM&q=85&s=64d9240e74b319d11c045fe323d4a472" alt="diagram" style={{ maxWidth: "620px", width: "100%" }} width="620" height="120" data-path="gantt/diagrams/reference/widget-parameters/data-mapping/diagram-1.svg" />
</Frame>

<Warning>
  If only one date field is mapped, the Gantt cannot calculate task scheduling. Tasks will appear at default positions without correct date representation.
</Warning>

## Recommended Field Types

For production use, configure proper Polarion custom fields with the recommended types:

| Field          | Recommended Type | Ad-Hoc Fallback | Notes                                              |
| -------------- | ---------------- | --------------- | -------------------------------------------------- |
| Start Field    | Date (Only)      | String          | Date fields provide native date picker in Polarion |
| End Field      | Date (Only)      | String          | Date fields ensure proper date validation          |
| Duration Field | Integer          | String          | Integer provides numeric validation                |
| Progress Field | Float            | String          | Float supports decimal precision (0.0 - 1.0)       |

<Tip>
  If a mapped custom field does not exist in Polarion, the Gantt automatically creates and uses a String ad-hoc custom field. While functional for testing, ad-hoc fields lack type validation and are not recommended for production use.
</Tip>

## Duration Precision

The `Duration Precision` parameter switches the entire Gantt between day-based and hour-based scheduling:

| Mode              | Duration Unit | Date Format | Use Case                                     |
| ----------------- | ------------- | ----------- | -------------------------------------------- |
| `Standard (Days)` | Days          | Date only   | Sprint planning, release scheduling          |
| `High (Hours)`    | Hours         | Date + Time | Fine-grained task scheduling, shift planning |

<Warning>
  Switching to `High (Hours)` precision changes the date format across the entire Gantt instance. All date fields display time components, and durations are stored in hours. See [Schedule in Hours Instead of Days](/gantt/guides/scheduling/hour-precision).
</Warning>

## Administration Defaults

Default data mapping values for new Work Items Gantt widget instances:

| Property                                         | Default          | Description                 |
| ------------------------------------------------ | ---------------- | --------------------------- |
| `nextedy.gantt.workitems.default.start_field`    | `gantt_start`    | Default start field name    |
| `nextedy.gantt.workitems.default.end_field`      | None             | Default end field name      |
| `nextedy.gantt.workitems.default.duration_field` | `gantt_duration` | Default duration field name |
| `nextedy.gantt.workitems.default.progress_field` | `gantt_progress` | Default progress field name |

## Configuration Example

A typical data mapping for a project using custom Polarion Date fields:

* **Start Field**: `plannedStart` (Date field)
* **End Field**: `plannedEnd` (Date field)
* **Duration Field**: `gantt_duration` (Integer field)
* **Progress Field**: `gantt_progress` (Float field)
* **Duration Precision**: `Standard (Days)`

With this mapping, the Gantt reads start and end dates from the plan fields, calculates duration automatically, and tracks progress via the float field.

## Plans Gantt Data Mapping

When **Show Plan Work Item** is enabled in the Plans Gantt, an equivalent set of data mapping fields appears for the work items displayed under each plan:

| Parameter                | Description                                  |
| ------------------------ | -------------------------------------------- |
| `Start Field` (Plans)    | Start date field for work items within plans |
| `End Field` (Plans)      | End date field for work items within plans   |
| `Duration Field` (Plans) | Duration field for work items within plans   |
| `Progress Field` (Plans) | Progress field for work items within plans   |

These follow the same rules and field type requirements as the Work Items Gantt data mapping.

## See Also

* [Work Items Gantt Widget Parameters](/gantt/reference/widget-parameters/work-items-gantt)
* [Plans Gantt Widget Parameters](/gantt/reference/widget-parameters/plans-gantt)
* [Schedule in Hours Instead of Days](/gantt/guides/scheduling/hour-precision)
* [Supported Field Types](/gantt/reference/supported-field-types)
* [Default Configuration Values](/gantt/reference/configuration/default-values)

<LastReviewed date="2026-07-07" />