在Golang中处理可选的布尔值

Question

I'm failing to understand how I can work around the problem I'm currently experiencing in my own application.

Imagine this example of a struct that models an incoming request and a function that puts the fields from that request into a database.

type NewBooleanRequest struct {
    RequiredString string `json:"requiredString"`
    OptionalBoolean bool `json:"maybeBoolean"`
}

func LogBooleanRequest(req NewBooleanRequest, db *sql.DB) {
    db.Exec("INSERT INTO log (booleanValue, stringValue) VALUES ($1, $2)", req.OptionalBoolean, req.RequiredString)
}

Now this obviously works fine if I know I will be given a value for all fields of my request model, but that's not a common requirement in reality. How do people generally model "optional" semantics for bool values given that bool has a zero value that is valid in essentially all contexts?

Answer 1

This question isn't specific to booleans, it's common for all NULLable types. The simplest solution is to use a pointer (*bool in your example). There are also Nullable values for common types provided by the sql package. sql.NullBool would be the one you want in this case.