Use the optional sample data

The separate mageb2b/customer-id-sample-data package is intended for development and disposable demonstrations. It creates a small set of sample customer accounts with CID-... values when Magento runs setup:upgrade.

Do not install it on a production store. The package contains fixed demonstration identities and passwords and is not a migration tool.

Install in a development environment

composer require mageb2b/customer-id-sample-data
php bin/magento module:enable MageB2B_CustomerIdSampleData
php bin/magento setup:upgrade

Verify the fixture records

php bin/magento sampledata:verify:customer-id

The command compares the installed records with the package CSV and reports missing or mismatched customer IDs.

Remove the fixture records

php bin/magento sampledata:reset:customer-id

The reset command asks for confirmation, deletes only the customer emails listed in its fixture CSV and removes the package's patch state so setup:upgrade can install the records again. Review the command output before continuing; deleting customers is destructive even in a development environment.

For migration of real customer numbers, use a controlled customer import or integration process instead.