Hi, 

Method gaiaGetVectorLayersList returns wrong fields names.

If I use spatialite binary, I've got the correct fields names (id_compt, type_compt):
spatialite> .schema compteur_routier
CREATE TABLE compteur_routier (
id INTEGER PRIMARY KEY,
geom POINT,
id_compt TEXT,
type_compt TEXT,
angle INTEGER,
id_tmp INTEGER
);

But If I use gaiaGetVectorLayersList method (thanks to demo5 example), I get wrong field name (id_compteur and type_compteur):
./demo5 -d ~/work/tmp/test_files/test_spl.sqlite -t compteur_routier       
SQLite version: 3.25.3
SpatiaLite version: 5.0.0-beta1



****** VectorLayersList (mode=OPTIMISTIC) *********
VectorLayer: Type=BasedOnSqlTable TableName=compteur_routier
	GeometryName=geom SRID=2154 GeometryType=POINT Dims=XY
	RowCount=7
	ExtentMin 848046.525865 / 6425228.263184
	ExtentMax 852051.441057 / 6429544.178129
	ReadOnly=FALSE Hidden=FALSE
		Field #0) FieldName=id
			IntegerValues=7 
			IntRange 1 / 7
		Field #1) FieldName=id_compteur
			TextValues=7 
			MaxSize/Length=4
		Field #2) FieldName=type_compteur
			TextValues=7 
			MaxSize/Length=9
		Field #3) FieldName=angle
			IntegerValues=7 
			IntRange 15 / 180
		Field #4) FieldName=id_tmp
			IntegerValues=7 
			IntRange 1 / 7
		Field #5) FieldName=geom
			BlobValues=7 
			MaxSize/Length=60



sample successfully terminated

You can download test files here : https://issues.qgis.org/attachments/download/13111/test_files.zip

At first, it was a reported bug in QGIS (https://issues.qgis.org/issues/19598) : the problem seems to come from the fact that the user rename the table, create a new one with new fields name, then populate new one with the old one data.

QGIS reads field name thanks to gaiaGetVectorLayersList method.

Regards,
Julien

demo5 does not run correctly in its present form:
./demo5 -d test_spl.sqlite -t compteur_routier -I-> main argc[5] argv[0][/home/mj10777/000_links/libspatialite_fossil/libspatialite.dustbin/examples/.libs/lt-demo5]

    if (argc > 1 || argv[0] == NULL)
	argc = 1;		/* silencing stupid compiler warnings */

-I-> main argc[5] 
-I-> main argv i[1] value[-d]
-I-> main argv i[2] value[test_spl.sqlite]
-I-> main argv i[3] value[-t]
-I-> main argv i[4] value[compteur_routier]

Field #1) FieldName=id_compteur
          TextValues=7 
	  MaxSize/Length=4
Field #2) FieldName=type_compteur
	  TextValues=7 
	  MaxSize/Length=9

0	id	INTEGER
1	geom	POINT
2	id_compt	TEXT
3	type_compt	TEXT
4	angle	INTEGER
5	id_tmp	INTEGER

gaiaGetVectorLayersList calls gaiaGetVectorLayersList_v4
There a SELECT is done against vector_layers_field_infos
returning:

0	id
1	id_compteur
2	type_compteur
3	angle
4	id_tmp
5	geom

• RenameTable (administration TABLEs will be adapted)
• create and fill new table from old table
• DropTable old table (administration TABLEs will be adapted)

• CloneTable create a copy of the TABLE with data
• DropGeoTable/DropTable old table (administration TABLEs will be adapted)

• create and fill new table from cloned table
• DropGeoTable/DropTable cloned table (administration TABLEs will be adapted)