ORA-01756: quoted string not properly terminated

[egun]

I'm getting the following error:
[Oracle][ODBC][Ora]ORA-01756: quoted string not properly terminated
Line (27): "set Query = dbexample.execute(sql)".

My code is:

Code:

valueHID = Datatable.Value("HID_out")
sql = "SELECT rev_id FROM bh INNER JOIN clue ON bh.clue_id = clue.clue_id WHERE h_id = " & valueHID & "'"

set Query = dbexample.execute(sql)
Output Query.GetString
msgbox Output

Can anyone help me out on this one? What do I need to add to the end of my sql statement?