0
我有一個表,其中有很多冗餘點,我想選擇不同的點使用(不同),並選擇一些行的平均值(如rscp)。 我們這裏有一個例子:AVG沒有給出正確的值 - Postgresql
| id | point | rscp | ci
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
| 1 | POINT(10.1192 36.8018) | 10 | 701
| 2 | POINT(10.1192 36.8018) | 11 | 701
| 3 | POINT(10.1192 36.8018) | 12 | 701
| 4 | POINT(10.4195 36.0017) | 30 | 701
| 5 | POINT(10.4195 36.0017) | 44 | 701
| 6 | POINT(10.4195 36.0017) | 55 | 701
| 7 | POINT(10.9197 36.3014) | 20 | 701
| 8 | POINT(10.9197 36.3014) | 22 | 701
| 9 | POINT(10.9197 36.3014) | 25 | 701
什麼,我想是這樣的表如下:(rscp_avg是冗餘點的RSCP的平均值)
| id | point | rscp_avg | ci
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
| * | POINT(10.1192 36.8018) | 11 | *
| * | POINT(10.4195 36.0017) | 43 | *
| * | POINT(10.9197 36.3014) | 22.33 | *
我想這一點,但它給了我一個錯誤的平均值!
select distinct on(point)
id,st_astext(point),avg(rscp) as rscp_avg,ci
from mesures
group by id,point,ci;
感謝您的幫助(^_^)