MFC SQL join

[kronski]

I am trying to use the MFC ODBC database classes to solve a particular problem. However, knowing only the basics, I am unable to figure out how to implement a recordset for SQL statements that will contain a "join" command. For example, I need to implement the statement:

select count(nameid), max(currentdate)
from events join eventday on events.dayid = eventday.dayid
group by eventday.dayid
order by eventday.dayid

This joins the tables "events" and "eventday". What is the procedure for doing something like this using MFC?

Thanks in advance.

[Thomas Ascher]

Hi. To execute SQL statements without deriving a new class from CRecordset, you can call CRecordset itself by supplying the SQL statement:

CRecordset set(pDatabase);
CString strSelect = "SELECT SUM(Field1) FROM TestTable", strValue;

set.Open(CRecordset::forwardOnly, strSelect, CRecordset::readOnly |
CRecordset::noDirtyFieldCheck | CRecordset::executeDirect);
set.GetFieldValue(0, strValue); // use GetFieldValue to get the field values, because
double dSum = atof(strValue); // we haven't derived a class with member variables
set.Close();