## Overview Prevent duplicate values ​​from being entered in the field. ## Limitations 1. Even if a record already contains duplicate values, you can turn on "Prohibit duplicates," but a check is performed when updating the record, and the update cannot be performed unless the value is changed. 1. Items not filled in are not checked for duplicates. 1. Cannot be set in "[ID Item](/en/manual/table-management-id)". 1. Cannot be set in "[Version Item](/en/manual/table-management-ver)". 1. Cannot be set in "[Comment Item](/en/manual/table-management-comments)". 1. Cannot be set in "[Check Item](/en/manual/table-management-check)". ## Prerequisites 1. "Site Administration Permission" is required to configure settings. ## Related Information [Table Management: Editor: Item Detail Settings](table-management-column-settings) [Table Management: Item: Title](table-management-title) [Table Management: Item: Classification](table-management-class) [テーブルの管理：項目：数値](table-management-num) [Table Management: Item: Date](table-management-date) [Table Management: Item: Description](table-management-description)