New Post: GenerateCategories and OpenFromQuery

Hello
I can use GenerateCategories with an ogrlayer created with OpenFromDatabase like this :

ogrIlot.OpenFromDatabase(cnxSpatialite, "geoilot_parcellaire", False)
ogrIlot.GenerateCategories("Exploitant", ctUniqueValues, 10, White, DarkBlue, ctSchemeRandom)

but it doesn't work with OpenFromQuery like this :

ogrIlot.OpenFromQuery(cnxSpatialite, "SELECT * FROM geoilot_parcellaire") 
ogrIlot.GenerateCategories("Exploitant", ctUniqueValues, 10, White, DarkBlue, ctSchemeRandom)

and there is no error...
have you a solution please ?
guen