One time each one - sql

Question

I have build my database ofcourse etc but I have problem with the code.I try to solve that
"Names of marines(one time each one) that have for reservation red boat and their have tonnage bigger than 200." and I did that.
Select distinct m.name
From marina m join reservation r on (m.mid, r.mid)
Where r.bid = (select b.bid from boat b where b.color = "red")
I tryed use that https://senseful.github.io/text-table/ but I failed so I post here if someone can help edited.That is my database.
drop table if exists reservation;
drop table if exists marina;
drop table if exists boat;
drop table if exists sailor;
create table boat
(bid integer not null constraint c_bid primary key,
bname varchar(40),
color varchar(40)
constraint c_color check (color in ('Red','Blue','Light Green','Yellow')));
create table marina
(mid integer not null constraint m_key primary key,
name varchar(40) not null,
capacity integer);
create table sailor
(sid integer not null constraint c_sid primary key,
sname varchar(40),
rating integer
constraint c_rating check (rating between 1 and 10),
age real constraint
c_age check (age < 18 OR age = 18));
create table reservation
(sid integer not null constraint f_key1 references sailor(sid) on delete cascade,
bid integer not null constraint f_key2 references boat(bid) on delete restrict
constraint c_bid check (bid not in (999)),
mid integer constraint f_key3 references marina(mid) on delete set null,
r_date date not null constraint c_date check (r_date > '02/04/1998'),
constraint p_key primary key(sid,bid,r_date));
INSERT INTO sailor(sid,sname,rating,age) VALUES (2, 'John', 6, 17);
INSERT INTO sailor(sid,sname,rating,age) VALUES (11, 'Mary', 10, 18);
INSERT INTO sailor(sid,sname,rating,age) VALUES (12, 'TH', 7, 14);
INSERT INTO sailor(sid,sname,rating,age) VALUES (13, 'John', 9, 18);
INSERT INTO sailor(sid,sname,rating,age) VALUES (1, 'Christin', 10, 17);
INSERT INTO sailor(sid,sname,rating,age) VALUES (15, 'Thod', 10, 13);
INSERT INTO sailor(sid,sname,rating,age) VALUES (16, 'Leonid', 5, 13);
INSERT INTO sailor(sid,sname,age) VALUES (17,'Left',17);
INSERT INTO sailor(sid,sname,rating,age) VALUES (19,'Polu',1,16);
INSERT INTO sailor(sid,sname,rating,age) VALUES (27,'Marinin',8,15);
INSERT INTO sailor(sid,sname,rating,age) VALUES (37,'Cos',8,14);
INSERT INTO marina(mid,name,capacity) VALUES(33,'Porto',300);
INSERT INTO marina(mid,name,capacity) VALUES(5,'Calam',105);
INSERT INTO marina(mid,name,capacity) VALUES(1,'Plat',32);
INSERT INTO marina(mid,name,capacity) VALUES(7,'Pos',19);
INSERT INTO marina(mid,name,capacity) VALUES(2,'Our',105);
INSERT INTO boat(bid,bname,color) VALUES(88,'Sof','Blue');
INSERT INTO boat(bid,bname,color) VALUES(17,'Ag','Light Green');
INSERT INTO boat(bid,bname,color) VALUES(13,'Panag','Yellow');
INSERT INTO boat(bid,bname,color) VALUES(1,'Αg.N','Red');
INSERT INTO boat(bid,bname,color) VALUES(72,'Christin','Red');
INSERT INTO boat(bid,bname,color) VALUES(19,'Dil','Light Green');
INSERT INTO boat(bid,bname,color) VALUES(77,'Αg.G','Blue');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(2,88,7,'1999-02-17');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(12,17,2,'1998-05-17');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(11,17,2,'1999-01-17');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(13,13,7,'2003-01-13');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(11,13,33,'2000-05-05');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,1,33,'2000-05-05');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,13,33,'2000-05-06');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,17,33,'2000-05-07');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,19,33,'2000-05-08');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,72,33,'2000-05-09');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,88,33,'2000-05-10');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(1,77,2,'2000-08-10');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(19,13,33,'1999-10-12');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(27,88,7,'2000-06-11');
INSERT INTO reservation(sid,bid,mid,r_date) VALUES(37,72,2,'2001-04-27');

Answer 1

This can be solved with an EXISTS sub-query:
select m.*
from marina m
where m.capacity > 200
and exists (select *
from reservation r
join boat b on r.bid = b.bid
where mid = m.mid
and b.color = 'Red')
where m.capacity > 200 only selects marinas with a capacity that is bigger than 200 (this is how I understand the "have tonnage bigger than 200")
The (co-related) sub-query then checks for reservations for each marina that were made for a red boat (that's how I understand the "that have for reservation red boat" part).
Online example