Add some practical exercises

[Gustry]

We need some practical exercises :

• [ ] Edition, with relation 1-n and/or n-m
• [ ] Publish a pie chart per municipalities in the popup, about points
• [ ] Search a cadastre number using French relations between municipalities, sections, and cadastre polygon.
• [ ] Publish as WMTS, this one is difficult, but having a small worksheet with a checklist

It's nice to provide an EDIGEO export as geopackage in a training for the last one

I assign myself, but others are welcome of course ! :)

[mdouchin]

• 3.16: create uuid regexp_replace(uuid(), '[{}]', '')

• Create values from existing values (categorization)

CASE
WHEN lower(trim("juveniles")) = 'oui' THEN 'oui'
WHEN lower(trim("juveniles")) = 'non' THEN 'non'
ELSE 'nsp'
END

Get the code of the corresponding glossary feature

• with aggregate, powerful: you can adapt the filter with complex expressions

aggregate(
    layer:='especes_chiro',
    aggregate:='max', expression:="cd_nom",
    filter:=trim("nom_scientifique")=trim(attribute(@parent,'espece'))
)

• with direct access if value are corresponding exactly:

attributes(
    get_feature( 'especes_chiro', 'espece', "espece")
)['cd_nom']

• Date conversion

to_date("date", 'dd/MM/yyyy')

• Get "parent" polygon id based on point vs polygon intersection

aggregate(
    layer:='commune',
    aggregate:='max', expression:="code_commune",
    filter:=intersects($geometry, buffer(geometry(@parent), 50))
)