在Golang中将数组插入Postgresql数据库

Question

我希望能够将一个bigints数组写入我在Go中用于历史记录的表中.不幸的是,我不能和我在做错误时sql: converting Exec argument #1's type: unsupported type []int64, a slice抛出.这是我正在做的,为简洁而编辑:

type Card struct {
    cid int64
}

type Transaction struct {
        tid, cardid int64
        productids []int64
        salepoint int
        cardkey string
}

func logPurchase(card *Card, t *Transaction) {
     _, err := db.Exec("INSERT INTO history VALUES ($1, $2, $3, $4)", rand.Int63(), t.productids, card.cid, t.salepoint);
}

这是我希望插入的表的结构: tid bigint primary key, productids bigint[] not null, cardid bigint not null, salepoint int

Answer 1

github.com/lib/pq自2016年8月6日起支持数组.OP的声明可以写成:

_, err := db.Exec(
    "INSERT INTO history VALUES ($1, $2, $3, $4)", 
    rand.Int63(), 
    pq.Array(t.productids),   // <------- 
    card.cid, 
    t.salepoint,
)

Answer 2

使用自定义类型实现database/sql/driver.Valuer:

type int64array []int64

func (a int64array) Value() (driver.Value, error) {
    // Format a in PostgreSQL's array input format {1,2,3} and return it as as string or []byte.
}