Tested

Starting with drivers that pass go-sql-test.

• https://github.com/mattn/go-sqlite3
• https://github.com/jackc/pgx
• https://github.com/lib/pq
• https://github.com/ziutek/mymysql
• https://github.com/go-sql-driver/mysql/

Design doc

pgx

jackc/pgx#1169 (comment)

type Status byte

const (
	Undefined Status = iota
	Null
	Present
)

type ACLItem struct {
	String string
	Status Status
}

stdlib

type NullString struct {
    String string
    Valid  bool // Valid is true if String is not NULL
}

• Have another null type for pgtype?