The same named parameter marker should not show repeatedly in the prompt window.
select :num from dual where 1 = :num or 2 = :num
shows 3 times 'num' in prompt window.
We have an open ticket to look into prompting only once for identical marker names. I will add your vote for it.
DbVisualizer 9.5.2 has just been released with a fix so that multiple identically named parameter markers are only prompted once.
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