Inner join, left join, right join, full join

[Test @ ora1] SQL> select * From A; No. Name ---- ---------- 1000 Zhang San 2000 Li Si 3000 Wang Wu [test @ ora1] SQL> select * from B; product NO. ---- ---------- 1000 TV set 2000 video recorder 4000 bicycle [test @ ora1] SQL> set null Null Value -- Here I define null as [null value] [test @ ora1] SQL> select. *, B. * From a inner join B on. no. = B. no.; No. name No. Product ---- ---------- 1000 Zhang San 1000 TV set 2000 Li Si 2000 video recorder [test @ ora1] SQL> select. *, B. * From a left join B on. no. = B. no; No. name No. Commodity ---- ---------- 1000 Zhang San 1000 TV 2000 Li Si 2000 video recorder 3000 Wang Wu null value [test @ ora1] SQL> select. *, B. * From a right join B on. no. = B. no.; No. name No. Commodity ---- ---------- 1000 Zhang San 1000 TV 2000 Li Si 2000 video recorder null value 4000 bicycle [test @ ora1] SQL> select. *, B. * From a full join B on. no. = B. no.; No. name No. Commodity ---- ---------- 1000 Zhang San 1000 TV 2000 Li Si 2000 video recorder 3000 Wang Wu null value 4000 Null Value Bicycle --- above, hope to help you.