================================================================================
cross join
================================================================================
SELECT name FROM products cross join items;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (from_item
            (from_table
              (identifier))))))))

================================================================================
join on
================================================================================
SELECT name FROM products join items on products.name = items.name;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (op_expression
              (identifier)
              (comparison_op)
              (identifier))))))))

================================================================================
join using
================================================================================
select name from products join items using(foo);
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))))))

================================================================================
natural join
================================================================================
select name from products natural join items;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier))))))))

================================================================================
inner join
================================================================================
select name from products inner join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
left join
================================================================================
select name from products left join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
right join
================================================================================
select name from products right join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
full join
================================================================================
select name from products full join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
left outer join
================================================================================
select name from products left outer join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
right outer join
================================================================================
select name from products right outer join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
full outer join
================================================================================
select name from products full outer join items on true;
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (true)))))))

================================================================================
many joins
================================================================================
select name from products
    natural join a
    cross join a
    join a on a.foo=b.foo
    inner join a using(foo)
    left join a using(foo)
    left outer join a using(foo)
    right join a using(foo)
    right outer join a using(foo)
    full outer join a using(foo)
    full join a using(foo);
--------------------------------------------------------------------------------

(source_file
  (select_statement
    (select_item
      (identifier))
    (select_from
      (from_item
        (from_table
          (identifier))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier))))
        (join_item
          (from_item
            (from_table
              (identifier))))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (op_expression
              (identifier)
              (comparison_op)
              (identifier))))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))
        (join_item
          (join_type)
          (from_item
            (from_table
              (identifier)))
          (join_condition
            (identifier)))))))