filterExpression

Type: String

The filterExpression property of the ExternalCollection class contains the string expression used to override the default filtering or the WHERE predicate defined for an external collection. Use this property to select a subset of records at run time.

The filtering expression should not contain the WHERE keyword, and it must be defined in terms of external column names and not the attribute names to which they are mapped. If the resultant SQL statement is not valid, an ODBC exception is raised.

The following example shows the use of the filterExpression property.

displayExtDBCustomers();
vars
    custs : CustomersByCityDict;
    cust  : Customers;
begin
    create custs;
    custs.filterExpression := "Customers.city = 'London' ";
    foreach cust in custs do
        write cust.contactName & " " & cust.city;
    endforeach;
epilog
    delete custs;
end;