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create table tbl1 (
name varchar(20),
amount int
);
create table tbl2 (
name varchar(20),
amount int
);
insert into tbl1 values ('Петр', 100),
('Вася', 200),
('Петр', 100),
('Вася', 200);
insert into tbl2 values ('Петр', 100),
('Вася', 200),
('Петр', 100),
('Вася', 200);
select * from tbl1;
select * from tbl2;
| name | amount |
|---|---|
| Петр | 100 |
| Вася | 200 |
| Петр | 100 |
| Вася | 200 |
| name | amount |
|---|---|
| Петр | 100 |
| Вася | 200 |
| Петр | 100 |
| Вася | 200 |
select name, amount from tbl1
union
select name, amount from tbl2;
| name | amount |
|---|---|
| Петр | 100 |
| Вася | 200 |
select name, amount from tbl1
union all
select name, amount from tbl2;
| name | amount |
|---|---|
| Петр | 100 |
| Вася | 200 |
| Петр | 100 |
| Вася | 200 |
| Петр | 100 |
| Вася | 200 |
| Петр | 100 |
| Вася | 200 |
select name, sum(amount)
from (
select name, amount from tbl1
union all
select name, amount from tbl2
) t
group by name;
| name | sum(amount) |
|---|---|
| Вася | 800 |
| Петр | 400 |