Creating a Reference Field Mapping for Legacy-ServiceNow migrations

Supported Vendor Platforms for Reference Field Mappings

Reference Field Mappings can be used whenever the source vendor platform is one of the following:

BMC Remedy

HP Service Manager

Atlassian Jira

Salesforce

Cherwell

RSA Archer

SQL Server

Oracle

 

When to use a Reference Mapping for Legacy->ServiceNow migrations

Reference Field Mappings should be used whenever the Target Field needs to be set based on a value retrieved from a previous Form mapping.  For example, if you are creating a mapping from the Remedy HelpDesk form to the ServiceNow Incident table, the SiteID field needs to be converted to the sys_id of the corresponding ServiceNow Location.  In this case, if you have previously defined a Form Mapping from the Remedy Site Form to the ServiceNow Location table then you can use a reference field mapping to set the required field value.

Creating a New Reference Field Mapping

To create a new Reference Field Mapping, first select the Target Field from the list of fields in the Field Mapping List, then select Reference from the New Mapping field below.  A new screen is then presented with the name of the target field displayed at the top in bold.  Using the above example, select Site ID as the source field.  

Next, select the referenced mapping using the menu on the ‘Use Key Mapping from’ field.  This provides a list of all previous mappings (with lower execution order than the current mapping).  Using the above example, the referenced mapping would be the Location Reference Form Mapping.

Note that the referenced mapping must have a Key Mapping defined in order to be used as a reference.  The key is used to correlate the source and target records, in this case between Remedy Sites and ServiceNow Locations.

Note that for BMC Remedy source servers, the Source Field provided should normally be the ID of the referenced record (in this case the Site ID, which identifies the site).

Populate with Record ID

When this option is selected for ServiceNow target servers, the sys_id is returned from the Target record (in the above example, this would be the sys_id of the corresponding Location record).

When this option is selected for BMC Remedy target servers, the field with ID=1 (usually called Entry-ID, Request Id or similar) is returned from the Target record.

Populate Using Mapping For

If you want to return a different field from the Target record, select the option Populate Using Mapping For, then select the field that you want from the drop-down list. This list is restricted to the list of mapped fields in the referenced mapping.  Please note that when migrating to a ServiceNow reference field, you should always use the sys_id

Defining No-Match and Multiple Match Actions

If there is no matching reference value found, you can define what action to take using the No Match Action field.  The options available are summarised in the table below. 

On No-Match Action	Description
Set Null	Sets the target field value to Null
Skip Record	This record will not be migrated and recorded as skipped.
Log Warning	The value will be set to NULL and a warning recorded.
Log Error	This record will not be migrated and recorded as 'Error'.
Set Default	The Default value is used to set the target field instead.

If Set Default is selected then the default value must be provided in the field below the Multiple Match Action field. It is not possible to use a different default value for multi match an no match actions.

Similarly, you can control the behaviour if multiple matches are found using the Multiple Match Action Field.  These are the same as for the No Match Action field with the additional option of ‘Use First’.  If this option is selected then the first matching record is used to set the target value.

Once you have selected the mapping, click on the Validate button to validate the selection without saving.  Then click on the Apply button to apply and save your changes.  If necessary, you can use the Revert button to revert back to the previous state of this mapping before the last applied change.