[gdal-dev] ogr2ogr (I)LIKE not caseINsensitive

[Even Rouault]

On jeudi 28 novembre 2019 16:09:28 CET Jan Heckman wrote:
> Hi everybody,
> According to docs <https://gdal.org/user/ogr_sql_dialect.html>, LIKE and
> ILIKE should be caseinsensitive.
> However, they are not.
> ogr2ogr plangebieden.shp -t_srs EPSG:28992 -dim 2 -spat 45000 405000 140000
> 485000 WFS:"http://afnemers.ruimtelijkeplannen.nl/afnemers2012/services"
> Bestemmingsplangebied -lco ENCODING=UTF-8 -where
> "BeleidsmatigVerantwoordelijkeOverheid LIKE 'Geme%'" produces empty output.
> The clue is that LIKE 'geme%'  (as in the DB 'gemeente'). does produce
> output.
> Replacing LIKE with ILIKE makes no difference.

Jan,

That's an interesting case.

OGR SQL indeeds consider LIKE and ILIKE are identical and case insensitive.

But... when issuing a -where to a WFS source, OGR turns the SQL into OGC 
Filter Encoding so that the filter is evaluated by the server for performance 
reasons. When doing so it uses the PropertyIsLike predicate, which is case 
sensitive by default. There's a matchCase attribute that could be set to 
false.

So I can see 2 options:

1) change the WFS translation code to set matchCase=false. Quite easy to 
implement. Some backward compatibility consequence for users of WFS sources 
that would have dependended on the current behaviour (case sensitivity)

2) more work. for WFS, have LIKE and ILIKE having two different translations. 
But if we do so, as we would need to add a new SWQ_ILIKE operator, and we 
should also probably make LIKE and ILIKE be distinct operations on a pure OGR 
SQL evaluation (client side). Which has some backward compatibility 
implication.

Even

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