I'm migrating from an SQL source in a D8 commerce site. Presently, I'm working on product and inventory data. I have one migration for product variations, one for products, and then 6 additional migrations for inventory tables all in a single migration group. (Inventory data migrations are dependent on the product/variation migrations.) Everything works properly when I run the migrations individually.
However, I have a strange problem when I run
drush migrate-import --group=my_inventory_group --execute-dependencies. The migration runs fully and reports that everything is OK. I get all the inventory data, products, and variations, but the commerce_product__variations table gets only a single record added, instead of the 1510 records it should have. That record references the first product item in my source data and one of its variations.
What works for me is executing the product and variation migrations individually, and then the rest of the group.
drush migrate-import my_variation_migration
drush migrate-import my_product_migration
drush migrate-import --group=my_inventory_group --execute-dependencies
Why can't I execute the migration for the entire migration group with the single command?