sql套用(100分)

query1.Close;
query1.sql.Clear;
query1.SQL.add('select sum(jbthf) from DB');
query1.sql.Add('where bjqh=(select qh from qh where thlb=1 and yys=1)');
query1.open;
edit1.text:=query1.Fields[0].asstring;

我以QH表中bjqh为条件，将DB表中适合条件的jbthf字段累加后，赋值给edit1,F9运行通过，但edit1无显示，请帮忙看一下！！

query1.Close;
query1.sql.Clear;
query1.SQL.add('select sum(jbthf) from DB');
query1.sql.Add('where bjqh in (select qh from qh where thlb=1 and yys=1)');//改成“in”试试
query1.open;
edit1.text:=query1.Fields[0].asstring;

谢谢！

query1.Close;
query1.sql.Clear;
query1.SQL.add(' select sum(jbthf) as AAAAA from DB ');
query1.sql.Add(' where bjqh in (select qh from qh where thlb=1 and yys=1) ');
query1.open;
edit1.text:=query1['AAAAA'];

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