Change sObject field type and deploy using API

Question

In this thread, there is a discussion about modifying a custom sObject's type. When I try to change the field's type in the Salesforce UI, I can see an error message with some references to the code. However, when I modify an sObject in my IDE and push it to the server, the field type has been modified (specifically, text to picklist).

Why are there no errors when deploying the modified object via the API? Or why are there errors when trying to do this from within the UI? Is this behavior documented anyplace?

Answer 1

Since your org is live, the existing references will prevent you from making these changes in your Org via the UI while there are active references to them in page layouts or other code like workflow rules.

Eclipse doesn't care as much about these things since it's not inside an active org and relies more on you to know what you're doing. It expects your Org to validate whether your object is valid when you deploy the changes you've made. Presumably, at the same time you made these changes, any code that referenced these fields, you've also changed from text fields to picklists as well. If not, you'd need to change your page layouts afterward or you'll discover that your Org has metadata issues or conflicts that you'll still need to resolve even though the deployment was successful.