I am trying to solve this database problems - mysql

Question

Hi I am trying to solve the problems below I have included what I have got already. the questions are below.
This is what I have done.
CREATE TABLE casino (
casino_id int, -- a primary key
);
CREATE TABLE games (
id int,
PRIMARY KEY (id),
FOREIGN KEY (casino_id) REFERENCES casinos (id) ON DELETE CASCADE
);
CREATE TABLE countries (
id int,
PRIMARY KEY (id),
FOREIGN KEY (games_id) REFERENCES games (id) ON DELETE CASCADE
);
Question 2:
SELECT *
FROM players
LEFT JOIN games
ON players.id = games.id AND
games.type LIKE ‘%SLOT%'
ORDER BY players.id
SELECT *
FROM players LEFT OUTER JOIN players ON players.id = games.id
WHERE games.type LIKE '%SLOT%'
ORDER BY players.id ```

Answer 1

This is one way of making it
Type is here only char, usually type should be a table, so that a games could be many types, but that would make the query even bigger
CREATE TABLE countries (
id int,
Country_name CHAR(20),
PRIMARY KEY (id)
);
CREATE TABLE players (
id int,
ref_country_id INT,
type CHAR(50),
PRIMARY KEY (id),
FOREIGN KEY (ref_country_id) REFERENCES countries (id)
);
CREATE TABLE games (
id int,
name char(50),
type CHAR(50),
PRIMARY KEY (id)
);
CREATE TABLE rel_country_games (
ref_country_id int,
ref_games_id INT,
FOREIGN KEY (ref_country_id) REFERENCES countries (id),
FOREIGN KEY (ref_games_id) REFERENCES games (id)
);
CREATE TABLE casino (
casino_id int,
casino_name char(100),
PRIMARY KEY (casino_id)
);
CREATE TABLE rel_country_games (
ref_casino_id int,
ref_games_id INT,
FOREIGN KEY (ref_casino_id) REFERENCES casino (casino_id),
FOREIGN KEY (ref_games_id) REFERENCES games (id)
);
INSERT INTO countries VALUES(1,'Brasil'),(2,'Uruguay'),(3,'MExico')
INSERT INTO players VALUES(1,1,NULL),(2,1,'SLOT'),(3,2,'SLOT'),(4,3,'POKER')
INSERT INTO games VALUES(1,'slotgame1','SLOT'),(2,'slotgame2','SLOT'),(3,'poker','POKER');
✓
INSERT INTO rel_country_games VALUES(1,1),(1,2),(2,2),(2,3),(3,1),(3,3)
SELECT DISTINCT p.id,c.Country_name,p.type,g.type
FROM players p INNER JOIN countries c ON c.id = p.ref_country_id
INNER JOIN rel_country_games rcg ON c.id = rcg.ref_country_id
INNER JOIN games g ON rcg.ref_games_id = g.id AND g.type = p.type
WHERE p.type = 'SLOT'
ORDER BY p.id
id | Country_name | type | type
-: | :----------- | :--- | :---
2 | Brasil | SLOT | SLOT
3 | Uruguay | SLOT | SLOT
db<>fiddle here
If you have difficulties to play around with this in your mind, simply make a simple example and test your ideas.