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Topic: Advanced Search cannot find records within a 100 km (Myriad) square

Advanced Search with a filter on 'Grid Reference' correctly finds all records of any precision within a 10 km square, e.g.
TL04 finds records with OSGB specified as any of: 
> TL04
> TL04Y
> TL0741
> TL078412
> etc.
This uses computed record attribute 'grid_ref10000'.

However,  Advanced Search finds nothing when only the 100 km square is specified, e.g.
TL reports "No records found for grid_ref:TL ..."
This is because the attribute 'grid_ref100000' either does not exist or is not used by Advanced Search.

If this is by design it should be noted on the search form, please!

David Hepper
Records Officer, British Dragonfly Society

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Re: Advanced Search cannot find records within a 100 km (Myriad) square

Hello David,

Thank you for reporting this issue.

When applying a filter for a 100km grid reference using the Advance Search, e.g., TL, it searches for records supplied with the specified 100km grid reference, rather than all records within the 100km grid.

For example, please see the occurrence search below which was completed using the Advance Search:

https://records.nbnatlas.org/occurrence … ab_mapView

However, a field for 100km grid references does exist and can be used to filter a occurrence search. See this example search:

https://records.nbnatlas.org/occurrence … ab_mapView

So I can log this as an issue to investigate further, please can I ask did you apply any additional filters to your search when filtering by the grid reference TL? As when I replicated this search, records were returned (all those supplied with a TL grid reference), but you have specified here that none were returned?

Thank you again for reporting this issue,

Kind regards,
Rhiann

Rhiannydd Stock
NBN Atlas Support Officer

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Re: Advanced Search cannot find records within a 100 km (Myriad) square

Thanks, Rhiann.

I kept it simple by setting no additional filters.

Your two links above are unintentionally the same, I think, but I understand the point you're making. They should be (at very simplest):
https://records.nbnatlas.org/occurrence … Ireland%22
to show only exact matches of 'TL' - under 2,000.
and
https://records.nbnatlas.org/occurrence … Ireland%22
to show all contained records within 'TL' - over 21 million.

The former 'exact match' URL is created by 'Advanced Search'. However this is inconsistent with handling by Advanced Search of all finer resolutions, which automatically include all contained records. It's this inconsistency that I'm reporting. Please make Myriad searches 'Containing' by default.

There could usefully be a radio button below the Grid Reference field to allow the user to specify 'Containing' or 'Exact match'.

Example of a finer resolution:
In Advanced Search enter a filter only on Grid Ref for 'TL04'. This generates URL:
https://records.nbnatlas.org/occurrence … 04&...
to show all contained records within 'TL04' - 550,000.

David Hepper
Records Officer, British Dragonfly Society

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Re: Advanced Search cannot find records within a 100 km (Myriad) square

Hi David,

Sorry about sharing the incorrect link, but glad that you still understood my explanation.

This is very helpful feedback, I will log your suggestions with the inconstancy issue around 100km searches using the Advance Search.

Apologies for this issue, and until this issue is resolved, we thank you for your patience.

Thank you very much your feedback.

Kind regards,
Rhiann

Rhiannydd Stock
NBN Atlas Support Officer