在sql语句中查询出了Expr1的值怎么把它与VC的变量等值？

[lovememememe]

CString str = " SELECT DATEDIFF(minute, ZPSJ, Departure_time) AS Expr1 FROM southAreaBak where CPHM ='"+card+"' ";

hr= m_Rs ->Open(_variant_t(str),_variant_t((IDispatch*)theApp.pConnection,true),adOpenStatic,adLockOptimistic,adCmdText);

[zaodt]

int nMinutes = 0;

_variant_t var;

var = m_Rs->GetCollect("Expr1");

nMinutes = var.intVal;

[shakaqrj]

_variant_t var = m_Rs->GetCollect("Expr1");
var.??
??你调试看看是哪个成员