sql error

I’ve started getting this sql error when generating an application (editable grid) :
SQL ERROR’s:
Field:cont_num_ select cont_num from woh_date where cont_num = {cont_num_}
()

cont_num and woh_date are fields in my mysql database.

In the file :

function SC_lookup_cont_num_($condicao, $campo)
{
$result = array();
$campo = substr($this->Db->qstr($campo), 1, -1);
$nm_comando = “SELECT cont_num, cont_num FROM woh_date WHERE (cont_num LIKE ‘%$campo%’)” ;
if ($condicao == “ii”)

I’m having trouble getting rid of the error. Any ideas? Thank you.

Please show the generated code of that function.