MySQL Query to combine two tables - mysql

Question

I'm trying to get a MySQL query to combine two tables. Both tables have a user_id and date column and the other columns are unique to each table. What I'm looking to accomplish is best explained with an image (imgur). I've tried various joins and unions and can't get the right combination. I've also tried searching stackoverflow but I'm likely not using the right terminology for what I'm looking to do.
The description of the tables in TEXT:
tablel
user_id date animals
1 9/15/2020 Lion
2 8/11/2020 Tiger
3 12/12/2020 Bear
table2
user_id date fruit
1 7/7/2020 apple
2 6/5/2020 pear
4 3/8/2020 peach
output
user_id date animals fruit
1 9/15/2020 Lion
1 7/7/2020 apple
2 8/11/2020 Tiger
2 6/5/2020 pear
3 12/12/2020 Bear
4 3/8/2020 peach

Answer 1

With UNION ALL you can achieve that
SELECT user_id, date, animals, fruit FROM
(
SELECT user_id, date, animals, '' as fruit
FROM table1
UNION ALL
SELECT user_id, date, '', fruit
FROM table2
) t
ORDER BY user_id, animals

Answer 2

You may also try FULL OUTER JOIN:
SELECT user_id, date, animals, '' as fruit
FROM table1
FULL OUTER JOIN table2
ON table1.user_id = table2.user_id AND table1.date = table2.date

Answer 3

-- use test;
-- drop table if exists table1;
create table table1(user_id int, `date` date, animals varchar(10));
insert into table1 values(1,'2020/09/15','Lion');
insert into table1 values(2,'2020/11/08','Tiger');
insert into table1 values(3,'2020/12/12','Bear');
-- drop table if exists table2;
create table table2(user_id int, `date` date, fruit varchar(10));
insert into table2 values(1,'2020/07/07','apple');
insert into table2 values(2,'2020/05/06','pear');
insert into table2 values(4,'2020/08/03','peach');
select
user_id,
`date`,
animals,
'' as fruit
from table1
union all
select
user_id,
`date`,
'',
fruit
from table2
order by user_id,`date`;
output:
+ ------------ + --------- + ------------ + ---------- +
| user_id | date | animals | fruit |
+ ------------ + --------- + ------------ + ---------- +
| 1 | 2020-07-07 | | apple |
| 1 | 2020-09-15 | Lion | |
| 2 | 2020-05-06 | | pear |
| 2 | 2020-11-08 | Tiger | |
| 3 | 2020-12-12 | Bear | |
| 4 | 2020-08-03 | | peach |
+ ------------ + --------- + ------------ + ---------- +

Answer 4

the more simple query to understand it would be :
SELECT * FROM tablel, table2 WHERE table1.user_id = table2.user_id
the second table need to have a foreign key, that have the id like the fisrt table, this query that I show you works like a INNER JOIN.