Variables (Magic xpa 4.x)

Variables are declared in the Data View section, and they are usually neutral. The data view is built on the server, but as the program interacts with the user, the values change. These changes are stored on the client and sent back for storage at the appropriate time, when the transaction is closed.

However, for some variables, every time the variable changes on the client, server access is required immediately. Such variables are called server-side variables. These variables have an "S" next to them, and are shown in a contrasting color, as shown in the image above.

This can happen if the variables are used in the Range/Locate of a Link. Each change of the variable value will execute the link again; hence there will be access to the server. In the example above, we have a Customer Code that is used to link to a Customer Record. If this Customer Code is used in an expression, it will cause that expression to be server-side.

In a Rich Client program, if the data view contains BLOB variables with lots of content, the BLOBs will be passed between the server and clients (like all other variables), and this might slow down the program.

It is advised not to define the BLOBs in the data view if they are not used, or you should create a new Batch task that handles them if they are to be used on the server side.