Stop multiple, repeated time series legend entries

Grafana Time Series Panel
1

Grafana v9.1.7: I have a time series which is populated from Questdb using a panel query. This query selects the following.

select 
  e.SequencerTs as time, (e.Price / 100000d) AS value, 'ext_trades' as series, 'SELL' AS side, 'ORDERADD' AS ordertype

and there is an overide that matches
value {series = ‘ext_trades’ , side = ‘SELL’, ordertype = ‘ORDERADD’ }

Depending on the time range this query returns multiple rows. I get the points plotted in grafana and a single legend entry with my chosen override Display Name.

When I add to the query like this

SELECT 
  CAST(o.Trade as String) as trade,
  to_str(o.SequencerTs, 'yyyy-MM-ddTHH:mm:ss.SSSUUUZ') AS strTime,
  o.SequencerTs AS time, (o.LimitPrice / 100000d) AS value, 'int_trades' as series, 'SELL' AS side, 'ORDERADD' AS ordertype

adding the tradeId & strTime value means I now get a legend entry for each point plotted - I realise this is because each of the newly added sql values returned has a different value for each row but I would like to know is there any way to limit the legend. I have tried adding a new override based on the query name but this still shows multiple legends.

Thanks for anyone who can shed some light