Postgres 10

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create table person (id int, name varchar(100), 
email varchar(100), accepted varchar(100));

CREATE TABLE

create table guest (id int, name varchar(100), 
accepted varchar(100),id_person int);

CREATE TABLE

insert into person values (1,'A',NULL,NULL);
insert into person values (2,'B',NULL,NULL);
insert into person values (3,'C',NULL,NULL);

INSERT 0 1

INSERT 0 1

INSERT 0 1

insert into guest values (1,'AGuest1',NULL,1);
insert into guest values (2,'BGuest1',NULL,2);
insert into guest values (3,'BGuest2',NULL,2);
insert into guest values (4,'CGuest1',NULL,3);
insert into guest values (5,'CGuest2',NULL,3);
insert into guest values (6,'CGuest3',NULL,3);

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

SELECT *
    FROM CROSSTAB (
        'SELECT p.name, g.name, g.name
        FROM person p JOIN guest g
        ON p.id = g.id_person
        ORDER BY 1,2')
        AS ("Person Name" varchar(100), "Guest 1 Name" varchar(100),
        "Guest 2 Name" varchar(100), "Guest 3 Name" varchar(100));

Person Name
Guest 1 Name
Guest 2 Name
Guest 3 Name

A
AGuest1
null
null

B
BGuest1
BGuest2
null

C
CGuest1
CGuest2
CGuest3

SELECT 3

Person Name	Guest 1 Name	Guest 2 Name	Guest 3 Name
A	AGuest1	null	null
B	BGuest1	BGuest2	null
C	CGuest1	CGuest2	CGuest3