for gpkg encoding library.

[gdey]

Currently the gpkg only support what is needed by us.

However, here is the sql from QGIS, there are some interesting triggers for the tile matrix:

			allSQLFROMQGIS = `

		CREATE TABLE IF NOT EXISTS gpkg_spatial_ref_sys  (srs_name TEXT NOT NULL,srs_id INTEGER NOT NULL PRIMARY KEY,organization TEXT NOT NULL,organization_coordsys_id INTEGER NOT NULL,definition  TEXT NOT NULL,description TEXT);
		CREATE TABLE IF NOT EXISTS gpkg_contents  (table_name TEXT NOT NULL PRIMARY KEY,data_type TEXT NOT NULL,identifier TEXT UNIQUE,description TEXT DEFAULT '',last_change DATETIME NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now')),min_x DOUBLE, min_y DOUBLE,max_x DOUBLE, max_y DOUBLE,srs_id INTEGER,CONSTRAINT fk_gc_r_srs_id FOREIGN KEY (srs_id) REFERENCES gpkg_spatial_ref_sys(srs_id));
		CREATE TABLE IF NOT EXISTS gpkg_ogr_contents (table_name TEXT NOT NULL PRIMARY KEY,feature_count INTEGER DEFAULT NULL);
		CREATE TABLE IF NOT EXISTS gpkg_geometry_columns (table_name TEXT NOT NULL,column_name TEXT NOT NULL,geometry_type_name TEXT NOT NULL,srs_id INTEGER NOT NULL,z TINYINT NOT NULL,m TINYINT NOT NULL,CONSTRAINT pk_geom_cols PRIMARY KEY (table_name, column_name),CONSTRAINT uk_gc_table_name UNIQUE (table_name),CONSTRAINT fk_gc_tn FOREIGN KEY (table_name) REFERENCES gpkg_contents(table_name),CONSTRAINT fk_gc_srs FOREIGN KEY (srs_id) REFERENCES gpkg_spatial_ref_sys (srs_id));
		CREATE TABLE IF NOT EXISTS gpkg_tile_matrix_set (table_name TEXT NOT NULL PRIMARY KEY,srs_id INTEGER NOT NULL,min_x DOUBLE NOT NULL,min_y DOUBLE NOT NULL,max_x DOUBLE NOT NULL,max_y DOUBLE NOT NULL,CONSTRAINT fk_gtms_table_name FOREIGN KEY (table_name) REFERENCES gpkg_contents(table_name),CONSTRAINT fk_gtms_srs FOREIGN KEY (srs_id) REFERENCES gpkg_spatial_ref_sys (srs_id));
		CREATE TABLE IF NOT EXISTS gpkg_tile_matrix (table_name TEXT NOT NULL,zoom_level INTEGER NOT NULL,matrix_width INTEGER NOT NULL,matrix_height INTEGER NOT NULL,tile_width INTEGER NOT NULL,tile_height INTEGER NOT NULL,pixel_x_size DOUBLE NOT NULL,pixel_y_size DOUBLE NOT NULL,CONSTRAINT pk_ttm PRIMARY KEY (table_name, zoom_level),CONSTRAINT fk_tmm_table_name FOREIGN KEY (table_name) REFERENCES gpkg_contents(table_name));
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_zoom_level_insert' BEFORE INSERT ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'insert on table ''gpkg_tile_matrix'' violates constraint: zoom_level cannot be less than 0') WHERE (NEW.zoom_level < 0); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_zoom_level_update' BEFORE UPDATE of zoom_level ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'update on table ''gpkg_tile_matrix'' violates constraint: zoom_level cannot be less than 0') WHERE (NEW.zoom_level < 0); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_matrix_width_insert' BEFORE INSERT ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'insert on table ''gpkg_tile_matrix'' violates constraint: matrix_width cannot be less than 1') WHERE (NEW.matrix_width < 1); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_matrix_width_update' BEFORE UPDATE OF matrix_width ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'update on table ''gpkg_tile_matrix'' violates constraint: matrix_width cannot be less than 1') WHERE (NEW.matrix_width < 1); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_matrix_height_insert' BEFORE INSERT ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'insert on table ''gpkg_tile_matrix'' violates constraint: matrix_height cannot be less than 1') WHERE (NEW.matrix_height < 1); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_matrix_height_update' BEFORE UPDATE OF matrix_height ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'update on table ''gpkg_tile_matrix'' violates constraint: matrix_height cannot be less than 1') WHERE (NEW.matrix_height < 1); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_pixel_x_size_insert' BEFORE INSERT ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'insert on table ''gpkg_tile_matrix'' violates constraint: pixel_x_size must be greater than 0') WHERE NOT (NEW.pixel_x_size > 0); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_pixel_x_size_update' BEFORE UPDATE OF pixel_x_size ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'update on table ''gpkg_tile_matrix'' violates constraint: pixel_x_size must be greater than 0') WHERE NOT (NEW.pixel_x_size > 0); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_pixel_y_size_insert' BEFORE INSERT ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'insert on table ''gpkg_tile_matrix'' violates constraint: pixel_y_size must be greater than 0') WHERE NOT (NEW.pixel_y_size > 0); END;
		CREATE TRIGGER IF NOT EXISTS 'gpkg_tile_matrix_pixel_y_size_update' BEFORE UPDATE OF pixel_y_size ON 'gpkg_tile_matrix' FOR EACH ROW BEGIN SELECT RAISE(ABORT, 'update on table ''gpkg_tile_matrix'' violates constraint: pixel_y_size must be greater than 0') WHERE NOT (NEW.pixel_y_size > 0); END;

			`

[ARolek]

@gdey I'm not sure what this issue is communicating. Is this the SQL that QGIS creates for a new gpkg, or is this what's needed by QGIS if we're creating a new gpkg?

[gdey]

Sorry, this is the sql that qGIS creates when it creates a new gpkg package. The triggers are useful for keeping the tile matrix tables updated. As well as keeping the index's updates. When we implement gpkg_tile_matrix_set it will be good to add these triggers. This is not part of the gpkg spec, and so it is nice to have the sql statements.