The Complete Guide to Migrating Your Odoo 16 Modules to Odoo 18

Upgrading your Odoo system entails transitioning a database from an older version, such as Odoo 16, to a more recent supported version, like Odoo 18. Regular upgrades are vital because each version brings new features, bug fixes, and security enhancements. It is highly recommended for all Odoo users to operate on a supported version.

An upgrade can be mandatory depending on your hosting type and new Odoo version. If no action is taken before the specified due date, an automatic upgrade will be triggered. Odoo’s Upgrade Team performs a silent test upgrade for every database that needs updating. However, it is strongly recommended to request an upgraded test database before proceeding with the actual upgrade.

Testing the upgraded test database is essential to ensure all features function correctly post-upgrade. If issues are found during testing, they should be reported to Odoo for resolution. The process of odoo upgrading a production database is similar to upgrading a test database, but the system will be temporarily unavailable during the upgrade.

This guide provides a step-by-step approach to migrating from Odoo 16 to Odoo 18, covering:

Pre-Migration Preparation – Assessing compatibility, backups, and testing environments.

Updating Custom Modules – Adapting code, views, and security rules for Odoo 18.

Data Migration Strategies – Ensuring seamless data transfer and integrity.

Post-Migration Validation – Testing workflows, training users, and ensuring compliance.

By following these best practices, you can minimize downtime and ensure a smooth transition to Odoo 18.

1.1 Backup Your Odoo 16 Database

A full and verified backup of the database and custom code is necessary before making any changes. This includes:

  • Database dump (PostgreSQL backup)
  • Filestore (attachments, documents, images)
  • Custom modules (local and third-party apps)

Example Command:

pg_dump -U odoo -W -F t odoo16_db > odoo16_backup.tar

1.2 Review Module Compatibility

A database cannot be upgraded if it contains custom modules that are not compatible with Odoo 18. Therefore, it is essential to:

Check for deprecated modules (e.g., web_kanban_gauge may no longer be supported).

Verify third-party apps (contact vendors for Odoo 18 compatibility).

Run a compatibility check on all custom and third-party modules.

Example Issue:

If your Odoo 16 module uses report_sale_order (now deprecated in Odoo 18), you may need to switch to account.report or another alternative.

1.3 Set Up a Staging Environment

Before migrating the production database, test the upgrade in a staging environment that mirrors your live setup. This helps identify:

  • Broken workflows
  • Data inconsistencies
  • Performance bottlenecks

Recommended Tools:

Docker (for containerized Odoo testing)

Odoo.sh (for automated staging deployments)

2. Updating Custom Modules for Odoo 18

Custom modules must be updated to ensure compatibility with Odoo 18. The upgrade process should parallel the upgrading of custom module source code to minimize delays.

2.1 Python Code Updates

Odoo 18 deprecates certain methods and introduces new APIs. Key adjustments include:

a) ORM Method Changes

Replace search() with search_count() where applicable.

Use create_multi() for bulk record creation instead of looped create().

Odoo 16 Example:

python

orders = self.env['sale.order'].search([('state', '=', 'draft')])

Odoo 18 Optimization:

python

draft_orders = self.env['sale.order'].search_count([('state', '=', 'draft')])

b) Decorator Updates

@api.multi is removed; use @api.model or @api.depends instead.

@api.onchange is replaced with computed fields in many cases.

2.2 XML and View Adjustments

Odoo 18’s UI improvements may require view updates:

a) Form View Changes

New widgets (e.g., may replace custom CSS).

Adaptive mobile layouts (ensure responsiveness).

Example:

Run HTML

b) List & Kanban Views

New grouping and sorting options.

Deprecated attributes (e.g., colors replaced by decoration-*).

2.3 Security & Access Rule Updates

Review ir.model.access.csv and ir.rule files to ensure compatibility with Odoo 18’s enhanced security model.

Example:

id,name,model_id:id,group_id:id,perm_read,perm_write,perm_create,perm_unlink  
access_custom_module,user_access,custom_module.model_custom,base.group_user,1,1,1,0

3. Data Migration & Post-Upgrade Steps

3.1 Using Odoo’s Migration Tools

Odoo provides built-in scripts for standard data migration, but custom data may need manual handling.

Steps:

Run odoo-bin -u all -d odoo18_db to update modules.

Use --load to import specific data files.

3.2 Validating Data Integrity

After migration, verify:

  • Accounting records (Journal entries, invoices).
  • Inventory moves (Stock quantities, transfers).
  • Partner data (Contacts, companies).

SQL Check Example:

SELECT COUNT(*) FROM sale_order WHERE state = 'draft';

3.3 Testing Business Flows

  • Ensure critical processes work:
  • Sales Order → Invoice → Payment
  • Purchase Order → Receipt → Vendor Payment
  • Manufacturing Orders → Stock Moves

3.4 User Training & Adoption

Training is essential after an upgrade to ensure users are familiar with new features. Key areas include:

  1. New dashboards
  2. Reporting tools
  3. Automation features

4. Post-Migration Best Practices

4.1 Security & Compliance
Ensure GDPR compliance in data handling.
Apply the latest security patches.

4.2 Performance Optimization
Monitor system performance post-upgrade.

Optimize database queries if slowdowns occur.

4.3 Post-Migration Support

seamless **odoo migration services include:**

  1. Bug fixes
  2. System training
  3. Ongoing maintenance

Conclusion & Next Steps

Migrating from Odoo 16 to Odoo 18 is a strategic move that enhances functionality, security, and performance. By following this structured approach pre-migration checks, custom odoo module updates, data validation, and user training you can ensure a seamless transition.

Call to Action

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