In an old Oracle Forms application, we have certain forms for providing report settings and starting the report. In many cases, a from/to range can be given, for example from Customernr. 1 - 10.
In some cases, brackets are used to "inform" the user that the to value is optional, and if empty only the from-value is used. If no brackets are shown, the empty to field is considered as infinite.

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In this example, the Order date on the To-side is considered infinite. If for example the 'customer nr'. on the to-side is empty, the report will be generated for the "From-customer". It is possible that the entire To-column is enclosed with brackets.
How can this be layout be reworked, including the previous options for the to-value. Are there other options so that this is not an issue anymore?