ORA-01756: quoted string not properly terminated

[Saket]

I observed that you have an extra single quote (') at the end, what is that for? i think this is causing the issue.
what is the type of field 'h_id'? if its numeric then do not add single quote in your query while passing values.
or if this is varchar then use variable in single quote single quote

Your query should be like

Code:

sql = "SELECT rev_id FROM bh INNER JOIN clue ON bh.clue_id = clue.clue_id WHERE h_id = " & valueHID

or

Code:

sql = "SELECT rev_id FROM bh INNER JOIN clue ON bh.clue_id = clue.clue_id WHERE h_id = '" & valueHID & "'"