```go
package main
import (
"database/sql"
_ "github.com/lib/pq"
"log"
"time"
)
func pollChanges() {
var id int
var name string
rows, err := db.Query("SELECT id, name FROM people")
if err != nil {
log.Fatal(err)
}
defer rows.Close()
for rows.Next() {
err := rows.Scan(&id, &name)
if err != nil {
log.Fatal(err)
}
log.Println(id, name)
}
err = rows.Err()
if err != nil {
log.Fatal(err)
}
}
var db *sql.DB
func main() {
var err error
db, err = sql.Open("postgres", "")
if err != nil {
log.Fatal(err)
}
defer db.Close()
for {
time.Sleep(1000 * time.Millisecond)
log.Println("Polling for changes...")
pollChanges()
}
}
```
Run:
```bash
PGUSER= PGPASSWORD= PGDATABASE=db_xyz PGSSLMODE=disable ./go-app
```
## Notes
- For a list of available connection parameters and environment variables, see:
https://www.postgresql.org/docs/9.0/static/libpq-envars.html
- Bind variables are named $1, $2, etc, not ?.
Using question marks instead of, e.g., $1 will result in the following error:
```
syntax error at or near ","
```
- Scan requires a pointer. Forgetting to add an ampersand (Scan(id) vs Scan(&id)) will result in the following error:
```
Scan error on column index 0: destination not a pointer
```