Beginner Question...

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James David Smith
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Beginner Question...
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CAMu32ABdWigZiqZv430BKDh0pye326Cert_yMv6K87x_hP4m2g@mail.gmail.com
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Beginner Question... James David Smith <james.david.smith@gmail.com>
Re: Beginner Question... Gavin Flower <GavinFlower@archidevsys.co.nz>
Re: Beginner Question... Tom Lane <tgl@sss.pgh.pa.us>
Re: Beginner Question... Michael Wood <esiotrot@gmail.com>
Re: Beginner Question... James David Smith <james.david.smith@gmail.com>
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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