Delta migration does not work

[PascalBrouwers]

Hi @victor-v-rad,

We migrated successfully from 1.9.0.1 to 2.1.2

After a while we wanted to have the new orders, customers etc into the Magento 2 but after running migrate:delta no new data was found. We did get some warnings:

In the old database mage_m2 tables are there. Any idea why it is not working?

[victor-v-rad]

Hi @PascalBrouwers

It could be in case you created (for testing purposes) new entities (orders/customers ... ) in Magento 2 after "data migration" but before "delta migration".

[PascalBrouwers]

Create no new customers after data migration. Though we did create 1 new product and a few new orders. Do I need to delete those?
If you want I can send the db's and the configuration.

[victor-v-rad]

It is better to make a fresh start by restoring your Magento 2 DB to its initial state

[PascalBrouwers]

I removed the extra products and orders that where added an ran the delta migration again, but got the same result. How does the delta migration work? Isn't there always a mismatch in entities because the M1 database has more entities?

[PascalBrouwers]

I ended up with doing a fresh install of Magento 2 and tried to retain the data that was made by using data upgrade scripts.

[victor-v-rad]

So have this worked out? The issue can be closed?

[PascalBrouwers]

Well, my question remains unanswered. Can you use the tool, make changes in data on M2 and then do a delta migration?

[victor-v-rad]

The tool was made for migraion to fresh installed Magento 2 otherwise issues can occur

[PascalBrouwers]

ah ok

[dfelton]

@PascalBrouwers To your question: "Well, my question remains unanswered. Can you use the tool, make changes in data on M2 and then do a delta migration?"

In my experience this depends on the nature of the changes on M2 database which you wish to perform prior to the delta migrations.

The deltas, do not track every change on the M1 database. For example you can go ahead and make all the changes you like to store configuration, as there is no Deltas for that.

The deltas are intended for (going from memory here) changes mostly regarding the following:

• Customer accounts
• Sales Information
• Catalog Inventory Stock changes.

This means you can make most the changes you want to other areas of the M2 database post initial migration without causing issues in your Deltas. Changes may include revisions to your Product Categories, Products themselves --again, the Deltas do track changes in inventory, so excluding that. I also do not recommend deleting products that were migrated, as the delta may blow up when attempting to update the inventory for deleted product(s) -- CMS Pages, Static Blocks.

Based off default configuration, I do not recommend doing any of the following on your M2 database after your initial migration if you plan to run Deltas with it's default configuration:

• Add/Remove products (on either DB. If you do add the product to both databases at the same time in the same order so that their entity_id on both databases match, this is only for inventory reasons, not attribute information reasons)
• Add/Remove customers
• Create any new orders
• Attempt to manage product inventory

[jeffb1a5]

checkout the last few comments on this thread:
#316

a magerun command to retro-actively populate the m2_cl tables in the M1 installation;