Need to buid validation in document record type feild

Summary:

We need to build validation in document of record custom feild. We are storing bank information in document records. We need a validation to check duplicate bank account number.

Content (required):

We need to build validation in document of record custom feild. We are storing bank information in document records. We need a validation to check duplicate bank account number.

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Code Snippet (add any code snippets that support your topic, if applicable):