A Date Check - To Narrow Down the Problem

I was facing an issue this week, wrong date of birth was shown for all the patients. When I look at closer, all the patients had same date of birth as "Jan/1/1970". Then I understood that "Jan/1/1970" must be the default date value of .net/sql server. It means somewhere we missed to assign the value for DOB field. Later we figured out, that it was a javascript issue. "Jan/1/1970" is the default date value of javascript. We missed to assign javascript DOB variable. So, as soon as you see "1970" instead of some other value, you can guess that something goes wrong in javascript.

.Net default date value is Jan-01-0001

Sql server default date value is NULL, starts from Jan-01-1753

Oracle default date value is NULL, starts from Jan-01-4712

Javascript default value is Jan-01-1970