read “SELECT *” columns into []string in go

In order to directly Scan the values into a []string, you must create an []interface{} slice pointing to each string in your string slice.

Here you have a working example for MySQL (just change the sql.Open-command to match your settings):

package main

import (
    "fmt"
    _ "github.com/go-sql-driver/mysql"
    "database/sql"
)

func main() {
    db, err := sql.Open("mysql", "user:pass@tcp(localhost:3306)/test?charset=utf8")
    defer db.Close()

    if err != nil {
        fmt.Println("Failed to connect", err)
        return
    }

    rows, err := db.Query(`SELECT 'one' col1, 'two' col2, 3 col3, NULL col4`)
    if err != nil {
        fmt.Println("Failed to run query", err)
        return
    }

    cols, err := rows.Columns()
    if err != nil {
        fmt.Println("Failed to get columns", err)
        return
    }

    // Result is your slice string.
    rawResult := make([][]byte, len(cols))
    result := make([]string, len(cols))

    dest := make([]interface{}, len(cols)) // A temporary interface{} slice
    for i, _ := range rawResult {
        dest[i] = &rawResult[i] // Put pointers to each string in the interface slice
    }

    for rows.Next() {
        err = rows.Scan(dest...)
        if err != nil {
            fmt.Println("Failed to scan row", err)
            return
        }

        for i, raw := range rawResult {
            if raw == nil {
                result[i] = "\\N"
            } else {
                result[i] = string(raw)
            }
        }

        fmt.Printf("%#v\n", result)
    }
}