Checkbox's "unchecked" is an empty string

for checkboxes, I noticed that when it is defaulted to "unchecked". When we try to query it, we get a return value of an empty string. When we use it as a filter criteria for a Query API, we could not get the record we want to retrieve. For example: "Select id, name from referral where R10118381 = '10195821' and delete_ = false" This query does not give us any results. We also tried the following. "Select id, name from referral where R10118381 = '10195821' and delete_ = ''" When we switched the default value to "checked" and queried it. We got the correct result. The query is similar to this: "Select id, name from referral where R10118381 = '10195821' and delete_ = 1" May I suggest that when saving a checkbox's value, instead of an empty string save 0 for unchecked for consistency. Or may we know how to use a checkbox's unchecked criteria in a query string.