In 2013.2 Release, there is a new feature added in the standard customization of NetSuite which is called "Custom Fields with Values Derived from Summary Search Results".
In this scenario, this new feature will be applied in order to capture the name of the user who approved the transaction. Below are the steps:
I. Create a transaction saved search.
1. Navigate to Reports > Saved Searches > All Saved Searches > New.
2. Click Transaction.
3. In the Criteria tab, add the filters below:
• Type is Return Authorization
• System Notes : Old Value starts with Pending Approval
• System Notes : New Value starts with Pending Receipt
4. In the Results tab, do the following:
• In the Sort By field, add System Notes : Set by.
• In the Columns tab, add the fields below:
- System Notes : Set by Maximum
5. In the Available Filters tab, add this filter below:
• Internal ID
6. Click Save & Run.
II. Create a custom body field.
1. Navigate to Customization > Lists, Records, & Fields > Transaction Body Fields > New.
2. Give it a name (e.g. Approved By)
3. Type= Free-Form Text.
4. Store Value= F.
5. In the Applies To tab, set Sale= T.
6. In the Display tab, set Subtab= Main.
7. In the Validation & Defaulting tab, select the transaction saved search in the Search field.
8. Click Save.