Fill table (PK column A, PK column B) with table of elements B, where column A does not have B – list pair

So, to me comes Table2 (PK Text) filled with elements FIRST, SECOND, THIRD, FORTH. I need to insert this element to TABLE1 where these elements are missing.

TABLE1

+----+--------+
| ID |  Text  |
+----+--------+
| A  | FIRST  |
| A  | SECOND |
| A  | THIRD  |
| B  | FIRST  |
| B  | THIRD  |
| C  | FIRST  |
+----+--------+

So ID A misses FORTH

| A  | FORTH |

Should be inserted

B misses SECOND and FORTH and so on

Answer should be something like that

+----+--------+
| ID |  Text  |
+----+--------+
| A  | FIRST  |
| A  | SECOND |
| A  | THIRD  |
| A  | FORTH  |
| B  | FIRST  |
| B  | SECOND |
| B  | THIRD  |
| B  | FORTH  |
| C  | FIRST  |
| C  | SECOND |
| C  | THIRD  |
| C  | FORTH  |
+----+--------+

Answer

You can cross join the texts from table2 with the distinct ids availabel in table1 and filter on the missing tuples with a not exists condition, like so:

insert into table1(id, text)
select t1.id, t2.text
from table2 t2
cross join (select distinct id from table1) t1
where not exists (
    select 1
    from table1 t11
    where t11.id = t1.id and t11.text = t2.text
)