Beginner Question...
От | James David Smith |
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Тема | Beginner Question... |
Дата | |
Msg-id | CAMu32ABdWigZiqZv430BKDh0pye326Cert_yMv6K87x_hP4m2g@mail.gmail.com обсуждение исходный текст |
Ответы |
Re: Beginner Question...
Re: Beginner Question... Re: Beginner Question... |
Список | pgsql-novice |
Hi everyone, Could someone help me with this question please? I have a table with four columns: - gps_id (primary key) - date_time - crimes_link (foreign key) - osgb36_geom The data in the table involves lots of gps tracks of different journeys. They are grouped into journeys by the 'crimes_link' field. So for example the first 50 rows have an identical 'crimes_link' field, then the next 50 rows a different value in 'crimes_link', then the next 50 rows a different one, etc. What I would like to do is to select the beginning location of each journey. This query gives me the date_time of the beginning of the journey: SELECT crimes_link, MIN(date_time) FROM camdengps3 GROUP BY crimes_link; However I need to add the osgb36_geom column into the query and am unable too. Any ideas how to do this please? Thank you James Smith
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