CONCAT combines specified values into one new value, appending them after each other.
p.full_name := CONCAT(p.first_name, " ", p.last_name)
It is common practice to have two separate information fields for a name - one for the first and one for the last name. If, once these data are collected, you want to treat the full name as one combined piece of information, use
CONCAT as in the example above.
" ", with a space in between the quotation marks, adds a space between the first name and last name. If you want to include a middle name in the full name, expression would look like this:
p.full_name := CONCAT(p.first_name, " ", p.middle_name, " ", p.last_name)