Oracle provides product support only for Oracle8 and later, so this article assumes that you're running Oracle8 or later.The Oracle Net8 library provides the client software that SQL Server needs.You need to understand that even if you configure an Oracle linked server in SQL Server Enterprise Manager, your SQL Server is a client of your Oracle database.Therefore, you must successfully install and configure Oracle client software on your SQL Server.

Column 3 is somehow materialized out of thin air, as it does not physically exists in the record on this page.

But starting with SQL Server 2012 the operation is, in most cases, instantaneous: only the table metadata is changed, no rows are being updated.

Lets look at a simple example, we’ll create a table with some rows and then add a non-NULL column with default values.

There can be a situation where you have to use a cursor, even though the experts say not to use cursors or to avoid them as much as possible.

But if you look closely, most of the time we use cursors to iterate through a row collection and update the same table.