[!SUMMARY] Table of Contents
The value you want to obtain thorough
Group Byshould groupvalueand then sortidbut the sorting does not work
example test database table: test
| ID | VALUE |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
if the data in a DB table does not have a meaningful order the
Group Bywill not work Using theLIMITclause imposes a restriction on the number of data rows thus changing the data content to have a meaningful order
select value
from (
select *
from test
order by id desc
limit 18446744073709551615
) group by value;| value |
|---|
| 3 |
| 2 |
| 1 |
select value
from (
select *
from test
order by id asc
) group by value;
| value |
|---|
| 1 |
| 2 |
| 3 |
select value
from (
select *
from test
order by id desc
) group by value;| value |
|---|
| 1 |
| 2 |
| 3 |