Concat function tolerant of null values

[Geojim]

When labeling with multiple fields, concat won't label if any field is null. Current workaround is to combine with coalesce function, but seems needless complcated.

[DelazJ]

I can't confirm on 3.10
@Geojim can you provide the version, OS you are using and probably expression and dataset you are using? Thanks.

[Geojim]

Using 3.10 on w10 x64.

Issue arises for multi-field labels, where one attribute is null meaning no other attributes are labelled for a particular feature. eg for a label
concat("column1",'\n',"column2")won't work if any column is null, whereas
coalesce("column1",'') || '\n' || coalesce("column2",'') would.

Same thing here https://gis.stackexchange.com/questions/122199/displaying-multiple-fields-as-labels-if-one-field-is-null-in-qgis

Bit messy imho.

[DelazJ]

I Still can not reproduce on 3.10 windows 10: concat("column1",'\n',"column2") result is not null if any of the fields is null.
The discussion you are linking to is 5 years old and five years are like decades in QGIS dev life 😄 . Meanwhile you got #2118 (and #1947 for background discussion) so I'm afraid your issue is local.

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