请教查询插入的问题。

[pan7861]

我的数据库中有两个表T1和T2
我得到几个字符串的值：
CSTRING A,B,C;打算分别插入到T1中，但是同时想根据A值在T2中查询得到D和E值并插入到T1表中
_variant_t strQuery,Holder;
strQuery = "select dd from T2 where aa = '"+A+"'";
theApp.ADOExecute(theApp.m_pADOSet, strQuery);
Holder = theApp.m_pADOSet->GetCollect("dd");
CString D = Holder.vt==VT_NULL?"":(char*)(_bstr_t)Holder;
strQuery = "select ee from T2 where aa = '"+A+"'";
theApp.ADOExecute(theApp.m_pADOSet, strQuery);
Holder = theApp.m_pADOSet->GetCollect("ee");
CString E = Holder.vt==VT_NULL?"":(char*)(_bstr_t)Holder;

strQuery = "insert into T1 (a1, b1, c1, d1, e1) values ('"+A+"','"+B+"','"+C+"', '"+D+"', '"+E+"')";
theApp.ADOExecute(theApp.m_pADOSet,strQuery);
上面那样写如何不对，该如何写代码