Sql question marks in insert statement

Question

This may seem a very rudimentary question but I am not clear about it. In my code I have a query

    "insert into CONTACTS (EMAIL, FIRSTNAME, LASTNAME, TELEPHONE) values (?, ?, ?, ?)"

What is the '?' in the values, is it to fetch the real time values?

Answer 1

This is coming from some prepared statement. Those question marks will be populated with values later on, before the query is executed.