Deleting all the data in Salesforce.
If you have a trial account of Salesforce, and at any time you decide to delete all the data including the sample data, that is, the data you stored in the Salesforce trial organization, follow these instructions:
1. Navigate to Setup | Data Management | Delete All Data.
2. Salesforce will request you to enter text to state that you understand all data will be deleted:
3. Click on the Submit button as shown in the preceding screenshot to complete this process.
Note: This feature is only available during the trial period.
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