I added to my SpatiaLite table (.osm-import with the "standard" QGIS-OSM-Plugin) two empty columns x and y (double) to define manually the position of my labels (data defined labeling). But after telling the layer about the x and y-column, all labels just disapears!
I tested it in different CRS and with different data types and lengths. I created the columns in QGIS (When I create them in DB-Manager or Qspatialite, they wont appear in the QGIS attribute table)
Im absolutely new to SQL databases!
Thats my table:
Creating a column with
ALTER TABLE "pelepo_300114_place" ADD COLUMN label_x integer
works but is NOT displayed in Qgis. (I tryed it with integer, numeric, float...)