各位大大，今天遇見一件很怪的事，有一個語法在SQL Analyzer可以執行，在SQL Explorar也可以執行，在BDE也可以執行，但為什麼在ADO就無法執行，語法如下：

RQuery:=TADOQuery.Create(nil);
With RQuery Do
Begin
RQuery.Close;
RQuery.SQL.Clear;
SQLSTR:='Select CAST(REPLACE(A.m_Revenue, '','','''') AS float) as DPA,CAST(REPLACE(B.m_Revenue, '','','''') AS float) as DPB,';
SQLSTR:=SQLSTR ' CAST(REPLACE(C.m_Revenue, '','','''') AS float) as DPC From Rooms_revenue A,Rooms_revenue B,Rooms_revenue C ';
SQLSTR:=SQLSTR ' Where A.DATUM=B.DATUM And B.DATUM=C.DATUM And A.DATUM=''2006/08/08'' And A.DP_No=''10'' And B.DP_No=''20'' And C.DP_No=''21''';
RQuery.SQL.Text:=SQLSTR;
RQuery.Open;
RQuery.First;
End;

請幫我看看吧，謝謝

TADOQuery 手動建立要帶入連線字串吧

ADO_Query := TADOQuery.Create(nil);
ADO_Query.ConnectionString := ConObject.ConnectionString;