Hi
To put it simply, Concat adds new rows to the table, while Join adds new columns.
By way of example, use concat when combining rows from multiple tables or files, or combining (for eg) sales and budgets into a single fact table.
An example of a join would be adding lookup information, such as adding in a customer name to a source that contains the customer ID.
Hope that helps
Jonathan
(These are simple examples. Strictly speaking, outer joins can result in more rows and joins can also cause a source row to be replicated if the join condition is not unique).
Logic will get you from a to b. Imagination will take you everywhere. - A Einstein
