Solution Guide for Migrating Oracle on UNIX to SQL Server - Willy .Net

<strong>Solution</strong> <strong>Guide</strong> <strong>for</strong> <strong>Migrating</strong> <strong>Oracle</strong> on UNIX to SQL Server on Windows 287Figure 17.6 shows all the properties of a data block.Figure 17.6Properties of a data blockControl BlockThe second type of block is the control block. The items in a control block are notassociated with the database, and its items do not relate to any columns within anydatabase table. The items in a control block are called control items. For example,buttons in a module can initiate certain actions and can be logically grouped in a controlblock. The control block is only a logical grouping and the physical or visual placementmay differ. It is also a mechanism to segregate the control block items from the items thatare dependent on the database. Control items are used to per<strong>for</strong>m functions, such asaccepting input from the user and displaying calculated values and look values.Program UnitsProgram units are part of <strong>for</strong>ms modules and they contain named procedures, functions,or packages. The program units are similar to the program units created in the librariesbut are local to the <strong>for</strong>m in which they are created. They are stored and executed on theclient with any embedded SQL passed to the database <strong>for</strong> processing. If this codecontains database interactions, then it needs to be converted to T-SQL. If it contains onlynon-database related code, then it needs to be converted to its equivalent inVisual Basic .NET.TriggersThe trigger object is a PL/SQL block executed on an event. Triggers can be owned by the<strong>for</strong>m module, a data block, or an item, depending upon their scope.