SQL INSERT INTO from multiple tables

Question

this is my table 1:

NAME       AGE        SEX        CITY             ID

Clara      22         f          New York         1
Bob        33         m                 


        

Answer 1

You only need one INSERT:

INSERT INTO table4 ( name, age, sex, city, id, number, nationality)
SELECT name, age, sex, city, p.id, number, n.nationality
FROM table1 p
INNER JOIN table2 c ON c.Id = p.Id
INNER JOIN table3 n ON p.Id = n.Id