package database/sql/driver
NotNull is a type that implements ValueConverter by disallowing nil values but otherwise delegating to another ValueConverter.
Golang database/sql/driver.NotNull type usage and ConvertValue function example
type NotNull struct {
Converter ValueConverter
}
func (n NotNull) ConvertValue(v interface{}) (Value, error) {
if v == nil {
return nil, fmt.Errorf("nil value not allowed")
}
return n.Converter.ConvertValue(v)
}
References :
https://golang.org/src/pkg/database/sql/driver/types.go
http://golang.org/pkg/database/sql/driver/#NotNull
http://golang.org/pkg/database/sql/driver/#NotNull.ConvertValue
