Batch Determination - search for batch with null characteristic value
I have Batch characteristics "Z-QA-ALERT" with data type "Char" & length 30 & is a part of Material-Batch class & also of selection class for batch determination. User when creates the batch in goods receipt, he enter some text (upto 30 characters) for this characteristics as a part of batch classification & Value assignment. This text is only maintained if the batch is having some issue. So, from business point of view if there is some text maintained to the specified characteristics means that there can be some issue with batch. So during batch determination (in case of issues/deliveries/stock transfers ) the business requirement is that batch determination should exclude such batches where characteristics "Z-QA-ALERT" is having some text maintained in it.
My question is how to write such condition in selection class so that so that batch determination should exclude such batches where characteristics "Z-QA-ALERT" is having some text maintained in it. I had tried with conditions as -
= ' '
= " "
etc.....but could not succeed. Can anybody guide me writing a condition with correct syntax ? Or if there are other options....