# Data Manager

## Content

The Data Manager is a powerful local data engine that sends requests to the server side, then binds the data to the GanttSheet when the data is ready. GanttSheet supports using a DataManager view as a data source.

![GS-flowchart](https://gcdocumentsitekrblob.blob.core.windows.net/document-site-files/images/df1fe1ee-eb3c-4da7-8c20-a0d8d2b7e734/GS-flowchart.3b4a69.png?width=536)

## Data Source Schema

A data source schema refers to the structure of data within a particular data source.
GanttSheet requires the following fields from the data source as task fields.

| **Task Field** | **Data Type** | **Description** |
| ---------- | --------- | ----------- |
| @cols=3:**Require Fields** |
| taskNumber | number | The task number. <br>It represents the unique number of each task.<br>Note: If not present, only the root task will be displayed in GanttSheet. |
| name | string | The task name. |
| duration | String/number/object | The task duration.<br>It contains value, unit, or time. |
| predecessors | string | The task dependency string. |
| mode | string | The schedule mode. <br>It supports two types of modes: ‘Auto’ and ‘Manual’.<br>The default type is ‘Auto’. |
| @cols=3:**Optional Fields** |
| start | date | The date when the task is started.<br>If the task schedule mode is ‘Auto’, this field is a calc field. |
| finish | date | The date when the task ended.<br>If the task schedule mode is ‘Auto’, this field is a calc field. |
| complete | number | The task completion percentage.<br>The percentage is calculated between 0 to 1. |

Here is a sample data source.

```
[
  {
    "id": 1,
    "taskNumber": 1,
    "parentId": null,
    "name": "Plan for Project Server 2013 deployment",
    "duration": "1 day", 
    "start": "21/12/23 8:00",
    "finish": "21/12/23 17:00",
    "predecessors": ""  
},
{
    "id": 2,
    "taskNumber": 2,
    "parentId": null,
    "name": "Prepare for deployment",
    "duration": "4 days",
    "start": "21/12/24 8:00",
    "finish": "21/12/29 17:00",
    "predecessors": "1"
  },
]
```