From Dwayne Wright PMP, PMI-ACP, CSM
Certified FileMaker Developer
Introduced with FileMaker Pro Advanced 8, the Data Viewer has been a very interesting option for the professional FileMaker developer. On the most basic level, the Data Viewer will show you data within fields, variables or defined calculations as you work with FileMaker Advanced. Particularly useful when used in tandem with the Script Debugger, another feature available only with FileMaker Advanced under its Tools menu. The FileMaker 9 Advanced version of the Data Viewer has a two tabbed interface to view Current and Watched data. The idea, like most tabbed interfaces, is that a user can quickly switch between the two views as needed.
The Current Tab area, added with FileMaker 9 Advanced, is usually used to see the values in fields or variables running in a script. If a value is used twice in the script, which is often the case in looping scripts, you will see the value refresh in the viewer as it changes. A very nice touch can be found in the bottom left area of the Current tab in the Data Viewer. This is the Add to Watch button. This can take a current value from the current tab and add it to the list of values a developer has decided to monitor in the Watch tab.
FYI... if you cannot see all the data in a current value, you do have options. If you double click it, it will come up in a new window. If you single click on it and hover the mouse above it, it will show you the value in a tool tip.
The Watch tab can be used to define what fields, calculations and variables you specifically want to keep track of. Setting up an expression to watch (fields, calculations and variables), is done via the add expression button found in the lower right area of the Data Viewer. This will bring up your traditional define calculation dialog box with a couple twists. These twists include an area to see the defined result of the expression and a button to refresh the valued results (called Evaluate Now).
A classic way to experience this evaluation is to use the Get(CurrentTimeStamp) function. This function returns the current date and time. You can add the calculation to the expression area and click the Evaluate Now button. You will see the current date and time as defined via your computers operating system. Wait a few moments and click it again to see the refreshed values.
Traditionally, the Data Viewer is used when something appears to go awry with record data during a script execution. A classic is example is that every now and then for no apparent reason, the script doesn’t work correctly. Well, there is a reason of course and it is likely some unique combination of record data, user interaction or security settings that is making the problem occur. This unique combination is rare and that is why the script misfires on a random basis. Using the Data Viewer, you can view the interactions with the record data as you try to reproduce the situation that results in the problem occurring.
Finally, there is an authentication feature in the Data Viewer. Many times, a developer has to troubleshoot a problem that occurs only in a lower level privilege set. So the developer needs to be logged into the database as a typical user when researching the problem. By default, the Data Viewer will only show the user what their security settings allow them to see. There is a button in the Data Viewer that allows the developer to authenticate themselves to see all the data, even if that developer is using a lower level of security in the database itself.
FYI... Many developers use the Data Viewer as a sandbox for their calculations. That is to say, they really are not that interested in viewing real data for the solution. They are using the expression area to build their complex calculations and click the Evaluate Now button and see what they get. This way they don’t have to add the calculation to the Manage Fields area and then look at a layout to see the results. They can simply work with their calculation, evaluate it, tweak it, evaluate it again, tweak it some more and ... well ... you get the idea.
FYI ... If you find that you really like the Data Viewer and Script Debugger, you might have to setup your computer with two monitors. One to see the database and one for tools such as these.
More info about the author and FileMaker in general, contact me at firstname.lastname@example.org.
© 2008 - Dwayne Wright - dwaynewright.com
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