Postgresql-函数获取行作为参数-如何访问该行的列？

Question

I have a function that must get as paramater a row of a table employee and returnd the age of the employee passed as parameter:

CREATE OR REPLACE FUNCTION getAge(employe employee) RETURNS int AS $$
begin
  return employe.age;
END; $$
LANGUAGE PLPGSQL;

I am trying to call the function like

select * from getAge('(1, Alexander, 34, null)' );

But it doesn't work. I am expecting that the function returns 34. How should I call the function properly?

Answer 1

I assume your employee table looks somewhat like this:

knayak=# \d employee
              Table "public.employee"
 Column |  Type   | Collation | Nullable | Default
--------+---------+-----------+----------+---------
 id     | integer |           |          |
 name   | text    |           |          |
 age    | integer |           |          |
 col4   | text    |           |          |

Simply call it as

select getAge ('(1,Alexander,34,null)');
 getage
--------
     34

Or use an table alias from a query as the input.

select getage(emp)
from employee as emp
where e.id = 1;

select * from func() is used for a SET/TABLE returning functions.

DEMO