You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mod.rs
    path of file: ./repos/sqlx/sqlx-core/src/any
    
    the code of the file until where you have to start completion: //! **SEE DOCUMENTATION BEFORE USE**. Generic database driver with the specific driver selected at runtime.
//!
//! The underlying database drivers are chosen at
    
    fn encode_by_ref(&self, buf: &mut AnyArgumentBuffer<'q>) -> crate::encode::IsNull {
        if let Some(value) = self {
            value.encode_by_ref(buf)
        } else {
            buf.0.push(AnyValueKind::Null);
            crate::encode::IsNull::Yes
        }
    }