Abstract classes allow for other classes to be derived from it.  However, an instantiation of the base class type (i.e. the abstract class) cannot be done.  To declare a class abstract, place the word 'abstract' between the access modifiers and the class keyword. 

Example:

public abstract class Vehicle
{
}

Within abstract classes you can have

 The following situation requires you to create 30 mL of a solution that contains 10% acid.  You have an abundance of 5% and 20 % acid solutions on hand to create the 30mL 10% solution with.  The question is, how many mL of each solution should be mixed together to form the 30mL 10% solution?

We can express the paragraph above by saying: 30mL of 10% solution equals x mL of 20% solution plus y mL of 5% solution.

If you are reading this it is because you have written a PROC SQL statement where you reference both a dataset that you created in an earlier step and a table that resides on an RDBMS (such as SQL Server, MySQL, Teradata, etc . .  .).

Well before you go any further I have to tell you that so far it is not possible to combine the results of a SAS data set and an DBMS table within one PROC-SQL-CREATE-TABLE-AS statement.

For example with the following code I would get an ODBC error saying that "object LIBRARY.SASDATASET1 is not an object in RDBMS ..."

The majority of tables that record transactional data contain many years of transactional data.  So if you wanted to compare sales in 2007 to sales and 2008, it may be a little tricky considering that the sales figure for any year are stored in the same column.

For example:

Welcome to my site.  My goal is to create a repository for various points of information in efforts to save work for individuals with similar endeavors as my own.  

I anticipate to publish my first articles in February 2009.  Please come back then. 

Thank you for visiting.

Oscar V.