Excel seems to provide an elegant solution to this by representing the "not set" value in the possible options. Something like this might work:
Query by "Checky Field": [*] Yes [*] No [*] Not Set You might assume "No" also includes "Not Set", if the fields are truly equivalent in meaning, and your users would prefer not to have to click both "No" and "Not Set" to fetch both R1 and R2 values. Or maybe I misunderstood the question =] Bryan Minihan -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Alan Wexelblat Sent: Friday, January 08, 2010 3:40 PM To: list IXDA Subject: [IxDA Discuss] The semantics of checkboxes and null values Yet another of my odd questions, feel free to skip if you don't care... I am attempting to design a query form to let people find things in a mixed set of records. For simplicity's sake let's say there are R1-type records and R2-type records. In the R1-type records there's a data value that's either Yes or No. In the R2-type records this data value is undefined or unset. Question: how do I form this query? If I give people a pair of checkboxes labeled "yes" and "no" then if they check yes they get only records with yes in that value; likewise if they check only no, they get records with no in that value. Checking both gives you records with either value. This works great for finding R1-type records, but how do I let people query for the R2-type records? I can send down a hidden "null" value so that when neither checkbox is checked I get the R2 records, but then how do people search for "all R1-type records with EITHER yes or no"? OK, I can make the null value visible, but that forces people to know about the structure of my database when they don't care about that. What they really want to say (I think) is that "I don't want this field to be part of the search criteria." In the fields that are text boxes we do that by leaving the box empty but leaving a checkbox empty means something different. I've thought about using tri-state boxes but that's awkward as hell and potentially leads to a lot of checking as there are many such data fields in this search form. I can't possibly be the first one to solve this problem - anyone know a good solution? TIA, --Alan ________________________________________________________________ Welcome to the Interaction Design Association (IxDA)! To post to this list ....... [email protected] Unsubscribe ................ http://www.ixda.org/unsubscribe List Guidelines ............ http://www.ixda.org/guidelines List Help .................. http://www.ixda.org/help ________________________________________________________________ Welcome to the Interaction Design Association (IxDA)! To post to this list ....... [email protected] Unsubscribe ................ http://www.ixda.org/unsubscribe List Guidelines ............ http://www.ixda.org/guidelines List Help .................. http://www.ixda.org/help
