How to get the weekday of a day in ubuntu terminal

Question

How do I get the weekday from a date in the ubuntu terminal?

For example I type in: 1990-01-22, I want to get an output that says for example Thursday if 22th day was a thursday.

Answer 1

Use %A:

$ date -d"1990-01-22" "+%A"
Monday

From man date:

   %A     locale's full weekday name (e.g., Sunday)