Delete zoom levels from an MBTiles file (set max zoom)

mbtiles_delete_zoom_level.sql

-- change 18 to whatever the max zoom level you want in your MBTiles

DELETE FROM images WHERE 
  tile_id IN (SELECT tile_id FROM map WHERE zoom_level > 18) AND
  tile_id NOT IN (SELECT tile_id FROM map WHERE zoom_level <= 18);

DELETE FROM map WHERE zoom_level > 18;

UPDATE metadata SET value = '18' WHERE name = 'maxzoom';

-- now run the VACUUM command

Hello,
I'm badly in need to change max. zoom level of my *.mbtiles file. Can you please help how to use these codes. I'm completely new in GistBox. I'm not sure where and how to use these codes. Please help me. Any help will make me grateful to you.

Regards,
Siddique

I'm doing this on a raster MBtiles which doesn't have an "images" table. If you're in the same situation, replace the first two statements with this:

DELETE FROM tiles WHERE zoom_level > 18;

DELETE FROM tiles_data WHERE 
  tile_data_id IN (SELECT tile_data_id FROM tiles_shallow WHERE zoom_level > 9) AND
  tile_data_id NOT IN (SELECT tile_data_id FROM tiles_shallow WHERE zoom_level <= 9);

DELETE FROM tiles_shallow WHERE zoom_level > 9;

UPDATE metadata SET value = '9' WHERE name = 'maxzoom';

VACUUM;