{c}
{disambiguate=SQL}
{{wiki=Set_operations_(SQL)#UNION_operator}}

Basic example tested on <SQLite> 3.40.1, <Ubuntu 23.04>:
``
sqlite3 :memory: 'select 1 union select 2'
``
output:
``
1
2
``

Two columns two rows:
``
sqlite3 :memory: <<EOF
select * from (values (1, 2), (2, 3))
union
select * from (values (2, 3), (3, 4))
EOF
``
output:
``
1|2
2|3
3|4
``

Note how duplicates are removed, to keep them we `UNION ALL` instead:
``
sqlite3 :memory: <<EOF
select * from (values (1, 2), (2, 3))
union all
select * from (values (2, 3), (3, 4))
EOF
``
output:
``
1|2
2|3
2|3
3|4
``
