[Qgis-user] Selecting records

[Pierre-Marie Le Dantec]

Hi Phil,

For manipulating dates throught SQL you should use ISO format
("YYYY-MM-DD").

Then, you can use a virtual layer with :

SELECT stationid, MAX(obs_date) FROM your_layer GROUP BY stationid

Cheers,

Pierma

2016-03-30 13:09 GMT+11:00 Phil (The Geek) Wyatt <phil at wyatt-family.com>:

> I must be thick, but I can't get my head around this in QGIS
>
>
>
> Data
>
> stationid_
>
> obs_date
>
> BK21
>
> 28/03/2016
>
> BK21
>
> 29/03/2016
>
> BK21
>
> 30/03/2016
>
> BL22
>
> 28/03/2016
>
> BL22
>
> 29/03/2016
>
> BL22
>
> 30/03/2016
>
> BL22
>
> 31/03/2016
>
>
>
>
>
> How do I select the Maximum date for each station ID?
>
>
>
> The data will be coming from a GEOJSON feed but I can also pull it as a
> shape file if needs be
>
>
>
>
>
> Cheers - Phil
>
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-- 
Pierre-Marie Le Dantec

73.64.34
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