Age() function not working with time.Time

Trying to use age() function from postgresql with DateOfBirth

type Person struct {
  ID int
  DOB time.Time
}

query := `SELECT id, AGE(dateofbirth) from person WHERE id = $1`

But got an error
> Unsupported Scan, storing driver.Value type []uint8 into type *time.Time

The age() function work if I just pass the DOB as string

type Person struct {
  ID int
  DOB string
}

But I want to check the validity of DOB so I use time.Parse("2006-01-02", DOB)

func createPerson(w http.ResponseWriter, r *http.Request) {
  err := r.ParseForm()
  if err != nil {
        log.Fatal(err)
  }
  dob := r.PostForm.Get("dob")
  birthday, _ := time.Parse("2006-01-02", dob)

  err = models.person.Insert(birthday)
  if err != nil {
        log.Fatal("Server Error: ", err)
        return
  }
  http.Redirect(w, r, "/", http.StatusSeeOther)
}

func getPerson(w http.ResponseWriter, r *http.Request) {
  id, err := strconv.Atoi(chi.URLParam(r, "id"))
  if err != nil {
	log.Fatal("Not found", err)
	return
  }
  person, err = models.person.Get(id)
  if err != nil {
      log.Fatal("Server Error: ", err)
      return
  }
  render.HTML(w, http.StatusOK, "person.html", person)
}

Your database driver is responsible for transforming the incoming data from the database into Go data types. I'll assume you're using pq, which has the following rules about data types:

> This package returns the following types for values from the PostgreSQL backend:
>
> - integer types smallint, integer, and bigint are returned as int64
> - floating-point types real and double precision are returned as float64
> - character types char, varchar, and text are returned as string
> - temporal types date, time, timetz, timestamp, and timestamptz are returned as time.Time
> - the boolean type is returned as bool
> - the bytea type is returned as []byte
>
> All other types are returned directly from the backend as []byte values in text format.

In PostgreSQL, the AGE function returns data type interval. This is not one of the directly supported data types, so pq processes it as []byte. That is why it works when you make DOB a string. Conversion between []byte and string in Go is trivial, so the driver is able to fill in the value.

The driver fails to fill the []byte into a time.Time value because it doesn't know what conversion routine to use. Actually, there is no direct conversion routine because interval represents a duration of time, while time.Time represents an instance of time. interval is more analogous to a time.Duration value. Still, the driver doesn't support any automatic conversion from interval to any type, and I'm not aware of a way to add a new conversion. You would have to implement the conversion yourself after fetching the data from the database.

You could also switch to the pgx driver, which supports an Interval type.