Default value for Context (context-Sensitive DFF) : how to bind variable in the WHERE clause

Summary:

Hi,

I am trying to configure a context sensitive DFF at Invoice header level (FlexCode=AP_INVOICE)

I want the context to be defaulted by the system from an SQL query on the AP_INVOICES_ALL table.

My question is regarding the SQL syntax.

I tried this at first:

SELECT INVOICE_NUM

 FROM  AP_INVOICES_ALL

 WHERE INVOICE_ID = :{PARAMETER.INVOICE_ID}

and ran into this error:

I want to understand how I can bind variable in the WHERE clause of my query so the current invoice information is fetched.

Thank you for helping,

Annie

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