Strange ADODB Behavior

Question

I recently had a very strange problem. The application is written in classic ASP, but I think this is the same case for every connection using ADO / OLEDB.

These are the connection parameters.

conn=Server.CreateObject("ADODB.Connection");
conn.Provider="Microsoft.Jet.OLEDB.4.0";
conn.Open("D:/db/testingDb.mdb");

In short, this code:

conn.Open("myconnection");
bigQuery = "...";
rs = conn.execute(bigQuery);
while (!rs.eof) {
    ...
    smallQuery = "..."
    rssmall = conn.execute(smallQuery);
    ...
    rssmall.close();
    ...
    rs.movenext();
}
rs.close();
conn.close();

It does not work if bigQuery returns more than a certain number of rows (in my case ~ 20). But if I use another connection for the inner loop, for example stealthyninja:

conn.Open("myconnection");
conn2.Open("myconnection")

bigQuery = "...";
rs = conn.execute(bigQuery);
while (!rs.eof) {
    ...
    smallQuery = "..."
    rssmall = conn2.execute(smallQuery);
    ...
    rssmall.close();
    ...
    rs.movenext();
}
rs.close();
conn2.close();
conn.close();

The problem disappears.

I use an Access database and IIS7, if that matters.

Does anyone have a logical explanation?

Answer 1

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