Improve data migration performance
Concept

In general, the more complex your data migration setup, the longer it takes to run the data migration. To make performance issues visible, you are advised to not only test with a few records. Also test with a larger number of records.
Besides the complexity level of your data migration setup, you have several options that you can consider to improve the performance of the data migration. To improve the performance of a data migration, you can apply the same performance improvement options as for an integration.

To further improve the performance of a data migration, you can apply external references.

On data migration from AX2012 to D365 FO, in D365 FO, new RecIds are created in D365 FO. These RecIds do not match with the AX2012 RecIds. An external reference links an AX2012 RecId to the related D365 FO RecId.

A table to be migrated can have fields that refer to a RecId of another table. To improve the performance, first migrate the referred-to tables. For these referred-to tables, make sure to generate the external references.

To generate external references, on the:

• Source document record setup, on the Line details, in the External reference field, indicate which field of the record contains the unique ID of the record in AX2012.
• Data migration message, on the record mapping, set the External reference field to Yes. As a result, when the message is run, after the D365 FO record is inserted, the external reference is created. External references are stored in the source connector application.

If external references exist for a table, to migrate a table that refers to the table with external references:

• No additional document setup is required.
• On the message, for the applicable field, define the External reference field option.

When the message is run, the referred-to RecIds are recognized as external references. Based on the external references, the applicable D365 FO RecIds are linked during import.

You want to migrate the CustTable. This table has a Party field that refers to the RecId of the DirPartyTable. To improve the performance, first migrate the DirPartyTable also generating the external references for this table. Then migrate the CustTable. The Party field is filled based on the existing external references for the DirPartyTable.

For a data migration from AX2012 to D365 FO, you can generate data migration messages. On message generation, if an AX2012 field refers to a RecId, it is assumed that the related record is already migrated. Therefore, on the migration message, the field mapping is automatically marked as 'External reference'.