Postgres 15

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select version();

version

PostgreSQL 15.0 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-10), 64-bit

SELECT 1

create table top_brands(name text);

insert into top_brands(name)
     values ('Ford'), ('Subaru'); 
    
select array_agg(name)
  from top_brands;

CREATE TABLE

INSERT 0 2

array_agg

{Ford,Subaru}

SELECT 1

create table dealership_sells(dealership text, name text); 

insert into dealership_sells(dealership, name) 
     values ('A', 'Ford')
          , ('A', 'Toyota')
          , ('A', 'Mazda')
          , ('B', 'Ford')
          , ('B', 'Subaru')
          , ('B', 'BMW')
          , ('C', 'Lexus')
          , ('C', 'Mercedes')
          , ('C', 'Aston Martin')
          , ('C', 'McLaren');
          
select dealership, array_agg(name) 
  from dealership_sells
 group by dealership; 
 
CREATE TABLE

INSERT 0 10

dealership
array_agg

B
{Ford,Subaru,BMW}

C
{Lexus,Mercedes,"Aston Martin",McLaren}

A
{Ford,Toyota,Mazda}

SELECT 3

with dealers(dealership, brands) as 
     (select dealership, array_agg(name) 
        from dealership_sells
       group by dealership
     ) --select * from dealers 
    , req_brands(brands) as 
      (select array_agg(name)
         from top_brands
      ) -- select * from req_brands 
select dealership 
  from dealers    d
  join req_brands r
    on d.brands @> r.brands; 

dealership

B

SELECT 1

dealership	array_agg
B	{Ford,Subaru,BMW}
C	{Lexus,Mercedes,"Aston Martin",McLaren}
A	{Ford,Toyota,Mazda}