Can anyone help me I have a portal that is filtered by the value in another field that is working fine but I want to show all the records when the field is blank instead of not showing any records is this possible?
Based on what you are describing, something like this should achieve what you are after;
This is the calculation that you would apply to the filter the portal records;
IsEmpty ( Table::FilterField )
PatternCount ( Portal::SearchField ; Table::FilterField ) > 0
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