Update query

[apffal]

Cannot update a table with this code

QString str;
int ord = n_ord->text().toInt();
query = QSqlQuery ("UPDATE leg SET dip = '"+ str +"'  WHERE n_ord = "+ ord +"  LIMIT 1");

QString str;
int ord = n_ord->text().toInt();
query = QSqlQuery ("UPDATE leg SET dip = '"+ str +"'  WHERE n_ord = "+ ord +"  LIMIT 1");

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"n_ord" is an integer primary key table field and "ord" its actual value

Can someone helps ?
Thanks in advance