Golang中的动态SQL选择查询

I am trying to build API, with database/sql and mysql driver, that will read data based on URL parameters.
Something like this

myapi.com/users?columns=id,first_name,last_name,country&sort=desc&sortColumn=last_name&limit=10&offset=20

countryScan

I don't need specific code, just some directions since I am learning Go and my background is PHP where this is easier to do.

Update

Thanks to answers I have partly working solution.
Here is code:

cols := []string{"id", "first_name", "last_name"}
vals := make([]interface{}, len(cols))
w := map[string]interface{}{"id": 105}

var whereVal []interface{}
var whereCol []string

for k, v := range w {
    whereVal = append(whereVal, v)
    whereCol = append(whereCol, fmt.Sprintf("%s = ?", k))
}

for i := range cols {
    vals[i] = new(interface{})
}
err := db.QueryRow("SELECT "+strings.Join(cols, ",")+" FROM users WHERE "+strings.Join(whereCol, " AND "), whereVal...).Scan(vals...)

if err != nil {
    fmt.Println(err)
}

b, _ := json.Marshal(vals)
fmt.Println(string(b))

SELECT id, first_name, last_name FROM users WHERE id = 105;

But how do I get data out to proper json object? Now it prints out strings encoded in base64 like this.

[105,"Sm9obm55","QnJhdm8="]