Create two tables, link them with left join
SQL Primer as Used in MySQL example from a Well House Consultants training course
More on SQL Primer as Used in MySQL [link]
Source code: joiner.sql Module: S152
drop table if exists main;
drop table if exists iused;
create table main (mode text, uses int default 0, c text);
create table iused ( f text );
insert into main (mode, c) values ("Train", "public");
insert into main (mode, c) values ("Bus", "public");
insert into main (mode, c) values ("Car", "private");
insert into main (mode, c) values ("Byke", "private");
insert into main (mode, c) values ("Ferry", "public");
insert into iused (f) values ("Train");
insert into iused (f) values ("Car");
insert into iused (f) values ("Ferry") ;
select * from main left join iused on main.mode = iused.f
where iused.f is NOT NULL;
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