How to handle N/A or Unknown Data
Posted on 2011-02-24
I have a field that takes numbers, a double type 100.45. However, the user says that sometimes the value is unknown. So, there are like two states for this field:
1. A number 0 to 1,000
2. Unknown or N/A value. Somebody has not measured it yet, so there is no value yet.
How can I design my table or the column to handle values like this and cover both states? I like to have a column with numbers only, and no chars in it to keep data integrity.
Any suggestions on how to handle this?