Sharepoint 2010. All list items disappeared after deployment

I have list definition in my solution. But af开发者_如何学编程ter each deployment items from this list disappead! Customer typed more than one hundred items why thay removed by deployment of same list? How to change properties of list definition to leave items?

In VS you can set the DeploymentConflict Resolution to Prompt, none or automatic.

But if you change your list, you will have to overwrite the existing list to deploy your changes. How will the deployment process know how to remap yhour fields?

You can export, deploy and import.

If you did not make any changes, set the resolution as required