It’s possible to activate or deactivate validation rules before migration to Salesforce on both Salesforce Classic and Lightning Experience platforms.
Note: Available in Essentials, Contact Manager, Group, Professional, Enterprise, Performance, Unlimited, Developer, and Database.com Editions.
Note: To define, change field validation rules, or view field validation rules you need to have Customize Application user permissions.
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So, to deactivate validation rules before migration to Salesforce, go through the following steps:
1. From the Setup, go to Object Manager and choose the relevant object
2. In the left sidebar, click Validation Rules.
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3. Click “Edit” from the drop-down menu.
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4. To deactivate the rule, deselect Active, and save your changes.
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