filter expression error returns true

[mathieubossaert]

Hi,

teaching QGIS on 3.4.15 today, we face a bug on MAC and windows (have to try on ubuntu) :
When we create a filter on a layer, if the expression contains an error ( for example a parenthesis not closed), the expression returns true so the layer is not filtered.

[gioman]

@mathieubossaert I cannot confirm on 3.10.2 on Ubuntu. Can you attach a sample dataset?

[mathieubossaert]

Thanks @gioman
You can try this filter :

"STATUT" = 'Préfecture de région'sdqsdqsdqsdqs

On that shapefile :
communes_occitanie.zip

By the way if this bug does not exist in 3.10 we will upgrade.

[gioman]

By the way if this bug does not exist in 3.10 we will upgrade.

@mathieubossaert if is ok in 3.10 I believe than there will be no fix for 3.4 as 3.10 is becoming very soon the next LTR (not totally sure but there will not be a new 3.4 point release).

[mathieubossaert]

ok Thanks. Let's close this issue.

[Gustry]

@mathieubossaert I cannot confirm on 3.10.2 on Ubuntu. Can you attach a sample dataset?

Did you try with a shapefile ? I can replicate this issue with any shapefile on master. (3.11)

[gioman]

Did you try with a shapefile ?

@Gustry actually I think I tested with a postGIS layer, if is confirmed in 3.10/master let's reopen.

[mathieubossaert]

this will be the proof for my students of the utility to report issues ;-)
In fact I use PostGIS at work so i did not rise this issue before.

[Gustry]

The feedback label can be removed ;-)

[gioman]

The feedback label can be removed ;-)

removed

[pigreco]

I did tests on 3.4.15, 3.10.2-2 and masters

for the shared shapefile I confirm.

Using a geopackage I get (on all versions):

With vector spatialite I don't confirm(on all versions)

OSGeo4W64 win 10

[uclaros]

This only fixes half the bug, which is when the user presses the test button. One can still click OK with a broken WHERE clause and have all features returned while he should not be able to. The root problem is probably mLayer->setSubsetString( txtSQL->text() ) not returning false on broken queries.

[roya0045]

What @uclaros said, setSubsetString should return a bool. I guess that this is used to validate the expression and could be used to validate the expression instead of checking the count.

[gioman]

This only fixes half the bug, which is when the user presses the test button. One can still click OK with a broken WHERE clause and have all features returned while he should not be able to.

Should this be reopened or there is already a new ticket?

[elpaso]

Feature request I would say. There's no validation for SQL in code.

[uclaros]

It's a bug in QgsOgrProviderUtils and it's consequences are described in this issue. I've got a PR ready for it so I say just reopen so it can reclose!

[elpaso]

Ok, I thought you were talking about validating the SQL syntax before sending it to the provider.