You might come accross a situation where you want to retrieve the values of all the rows concatenated and stored in one variable. Here is the solution. Lets say you have a table called tblCustomerOrders which has CustID and OrderID. You now want all the OrderIDs for a particular Customer to be stored in one variable with comma delimited. e.g. For CustID = 1001, OrderID="1,2,3,4,5,6,7..and so on". Here is how you do it.
For most DBAs, normalization is an understood concept, a bread and butter bit of knowledge. However, it is not at all unusual to review a database design by a development group for an OLTP (OnLine Transaction Processing) environment and find that the schema chosen is anything but properly normalized. This article by Brian Kelley will give you the core knowledge to data model.