Troubleshooting: Filtered Strings in Data Workflow

Issue

With the Filter operator, filtering strings that contain only numbers might lead to errors in your Data Workflow. If you encounter these errors, try the solutions listed below.

Solutions

Possible solutions to troubleshoot filtered string errors in your Data Workflow are:

Convert a number to a string by adding an artificial letter to your Data Workflow's argument.
Convert a number to a string by using a Filter Operator.

Adding an Artificial Letter to Your Argument

The first option is to append a letter to the beginning of your filtered field of numbers. Instead of entering an argument value of 12345, it’s better to enter something like T12345. Now, the Filter operator looks at this value as a string instead of a number. For example, concatenate a string of numbers (A) from a table. In your Filter operator, append a letter into your Formula/Expression: =CONCATENATE('T',A).

In the Module Builder, hover over your Data Workflow component.

A 5-button toolbar displays above the component on hover-over.

Using the toolbar, click the (Settings) button.

On your Data Workflow canvas, find your Filter operator.

Configure the Filter operator's Info window as follows:

Setting	Category
Category	Formula Value
Label	Concat Filter
Formula/Expression	=CONCATENATE('T',A)

Click Save.

Save your module.

Converting a Number to a String Using a Filter Operator

Another option is to check your argument. If the argument is a string, the filter works correctly. If the argument isn’t a string, you can run a formula to make the value a string. For example, you can use a combination of IF and STRINGIFY equations. In the expression field of your Filter operator, the equation looks like this: =IF(ISNUMBER(_arg),STRINGIFY(_arg),_arg). The first part of the equation is a True/False question to determine if your argument is a string or not. If True, the filter operation proceeds. If False, the value is cast into a string before being filtered.