Error in Casting date postgreSQL

Question

I'm trying to cast a varchar into a date with this following code, and the following error is outputting, any idea why?

ALTER TABLE import.employee
ALTER COLUMN birth_date
TYPE date
USING (birth_date::date);

---

    ERROR:  date/time field value out of range: "05/29/1960"
HINT:  Perhaps you need a different "datestyle" setting.
********** Error **********

ERROR: date/time field value out of range: "05/29/1960"
SQL state: 22008
Hint: Perhaps you need a different "datestyle" setting.

Answer 1

Set the datestyle before:

set datestyle = mdy;

Answer 2

If you need to get the ::date from birth_date, first give the DATE format to your field using the given functions in Data Type Formatting Functions docs.