Create a new DataTable

Step 1: Create a new Data Source

A prerequisite for creating a datatable is to have a data source for a database table which the datatable will be based on. In this example, we will be using the incident table as the data source.

Step 2: Create a new DataTable

Under the Administrator menu item, click on Datatables. Then click on the "New" button.

For the "Name" field, enter a unique name for the datatable. In this example, we will be using active_incident.
for the "GraphQL Shcema" field, select the Task schema as any table that inherits from the task table will use this schema.
for the "Data Source" field, select the incident data source that we created in the previous step.

Step 3: Configure the DataTable

When we open up the newly created datatable, we will see the following.

The "Name" field is the name of the datatable.
The "Data Source Type" field is the type of the datatable.
The "Data Source" field is the data source that we created in the previous step.

Below that we see:

A "Selectable" checkbox. This option indicate if records can be selected from the datatable.
A "Filter" button. This will open up a filter dialog where we can write (server side) javascript code to return a final encoded query string that will serve as the base filter for the datatable.
A "Script" button. This will open up a dialog where we can write (clident side) javascript code that can be used in the datatable column's advance configuration.
The "First Column" This column with the header "Available" contains all the field for the incident table.
The "Second Column" This column contains a list of fields that we can add to the datatable.
- By default, the sys_id field is selected.
The "Third Column" This column will display the configuration of the selected field from the "Second Column".

Step 4: Configure the Column

Continuing from Step 3, we will add two additional fields, number and short_description to the datatable. Once added, lets click on the gear icon on the number field.

There are a few configuration options that we can set for the number field.

"Pin" This determines if the field will be displayed in the datatable. There are certain instance where we want to add a field to the datatable but we don't want it to be displayed, hence we can unpin the field. For this example, we will be pinning the number field.
"Sort" This is a boolean value that determines if the field can be sorted.
"Search" This is a boolean value that determines if the field can be searched. For this example, we will be enabling the search for the number field.
"Search Default" This is a boolean value that determines at default state, this field will be selected in the search bar.
"Sort Default" This is a boolean value that will be sorted on when the datatable is loaded.
"Editable" This is a boolean value that determines if the field can be edited directly from the datatablelist view.
"Column Label" This is the label that will be displayed in the datatable.
"Display Type" In ServiceNow, there is a concept of value and display value. This is especially useful when dealing with reference, choice, date, etc. If we want to display the actual database value, we can select "Value" otherwise we can select "Display" for a more user friendly value.
"Search Field" This field most of the time will be left defaulted to the selected field name. However, if we want to search on a different field, we can set it to a different field name.
"Sort Field" This field most of the time will be left defaulted to the selected field name. However, if we want to sort on a different field when this field column is sorted, we can set it to a different field name.
"Advance" This field most of the time will be left defaulted to the selected field name. However, if we want to filter on a different field when this field column is filtered, we can set it to a different field name.