How to write such query?

Question

How do you programming in SQL, I don't understand nothing in it. :)

Table1:

+-----------+----------+------------+
| id        | key      | page       |
+-----------+----------+------------+
| 1         | A        | 123        |
| 2         | B        | 456        |
| 3         | C        | 777        |
+-----------+----------+------------+

Table2:

+-----------+----------+------------+
| id        | key      | page       |
+-----------+----------+------------+
| 1         | A        | 123        |
| 2         | B        | 456        |
| 3         | C        | 111        |
+-----------+----------+------------+

I have 2 tables. We can see that they have fields with the same 'key' (A, B, C). How can I filter 'page' column's value which are differ in Table1 and Table2.

So, in page column: 123=123, 456=456, 777<>111 ==> I want such table as Result:

NEW Table:

+-----------+---------------------+---------------------+
| id        | id & page_table1    | id & page_table2    |
+-----------+---------------------+---------------------+
| 1         | 3   777             | 3    111            |
+-----------+---------------------+---------------------+

Answer 1

@LukazSzozda's comment seems to be the right answer. But if you actually want exactly those three comments in the result, you can concatenate them with the concat function, like this

select a.id,
       concat(a.id, ' ', a.page)
       concat(b.id, ' ', b.page),
from Table1 a
join Table2 b
     on a.id = b.id
     and a.key = b.key
where a.page != b.page