ORA-02287: sequence number not allowed here

Question

I am trying to select values from two tables and insert them into one table and calculate the number of placements in total per year. I keep getting an error saying sequence

Answer 1

Do it like this You can use the sequence like this, For the group by part i recommend you follow the other answer from @Tony INSERT INTO placement_cal ( cal_id.nextval , EXTRACT(YEAR FROM start_date) , count(placement_id) FROM placement group by year);

INSERT INTO placement_cal (
cal_id.nextval  , EXTRACT(YEAR FROM start_date) , count(placement_id)
FROM placement_two
group by year);