Golang Postgresql数组

Question

If I have a table that returns something like:

id: 1
names: {Jim, Bob, Sam}

names is a varchar array.

How do I scan that back into a []string in Go? I'm using lib/pg

Right now I have something like

rows, err := models.Db.Query("SELECT pKey, names FROM foo")
for rows.Next() {
            var pKey int
            var names []string
            err = rows.Scan(&pKey, &names)
}

I keep getting:

panic: sql: Scan error on column index 1: unsupported Scan, storing driver.Value type []uint8 into type *[]string

It looks like I need to use StringArray https://godoc.org/github.com/lib/pq#StringArray

But, I think I'm too new to Go to understand exactly how to use: func (a *StringArray) Scan(src interface{})

Answer 1

You are right, you can use StringArray but you don't need to call the

func (a *StringArray) Scan(src interface{})

method yourself, this will be called automatically by rows.Scan when you pass it anything that implements the Scanner interface.

So what you need to do is to convert your []string to *StringArray and pass that to rows.Scan, like so:

rows, err := models.Db.Query("SELECT pKey, names FROM foo")
for rows.Next() {
            var pKey int
            var names []string
            err = rows.Scan(&pKey, (*pq.StringArray)(&names))
}