B4J Question ExecQueryAsync returns closed resultset

[Jmu5667]

Hello

I am using the following:

sSQL = "some sql query"
Dim SenderFilter As Object = pConn.ExecQueryAsync("SQL", sSQL, Null)
Wait For (SenderFilter) SQL_QueryComplete (Success As Boolean, rs As ResultSet)
if Not(rs.NextRow) Then
    ' do something else
else
    ' do this code
end if
rs.close

I have found the if no rows are returned from the query the resultset appears to be closed on return, so the 'if Not(rs.NextRow) Then' failes with an error, com.microsoft.sqlserver.jdbc.SQLServerException: The result set is closed.

Is this normal ?

Regards

John.

 

[DonManfred]

If there are no results the Resultset is not Initialized.

Wait For (SenderFilter) SQL_QueryComplete (Success As Boolean, rs As ResultSet)
if rs.isInitialized then
    if Not(rs.NextRow) Then
        ' do something else
    else
        ' do this code
    end if
    rs.close
else
    ' Do something else as the query returns 0 Results.
end if

 

[Jmu5667]

I get the same error when checking if the resultset is initialized

 

[agraham]

I get the same error when checking if the resultset is initialized

That sounds strange, assuming you are using the same code as DonManfred. Isinitialised is a B4J function that merely checks whether the wrapped ResultSet object is null or not. I wouldn't expect it to be capable of returning a SQLServerException as it doesn't touch the object itself.

  public boolean IsInitialized() {
    return (this.object != null);
  }

 

[Jmu5667]

That sounds strange, assuming you are using the same code as DonManfred. Isinitialised is a B4J function that merely checks whether the wrapped ResultSet object is null or not. I wouldn't expect it to be capable of returning a SQLServerException as it doesn't touch the object itself.

  public boolean IsInitialized() {
    return (this.object != null);
  }

Yep, strange indeed. I dont know why the rs is return as closed. It is initialised, as I have checked that. It is the rs.nextrow that cause's the exception.

 

[agraham]

If there are no results the Resultset is not Initialized.

So this assumption is wrong then?

 

[Jmu5667]

So this assumption is wrong then?

Yes, it would appear to be incorrect after testing it.

 

[Erel]

This is not the expected result. Are you sure that you are not closing the database before the result is ready?

 

[Jmu5667]

This is not the expected result. Are you sure that you are not closing the database before the result is ready?

I think you maybe right, it could be to do with the use of resumable subs.

 

[Erel]

Tip: never close the SQL object.

 

[Jmu5667]

Tip: never close the SQL object.

I always use the connection pool