CREATE TABLE IF NOT EXISTS mapitem(
  ename PRIMARY KEY, name TEXT NOT NULL, addr TEXT, lon REAL, lat REAL
);

CREATE TABLE IF NOT EXISTS maptype(
  ename, maptype TEXT,
  FOREIGN KEY(ename) REFERENCES mapitem(ename)
  ON DELETE CASCADE ON UPDATE CASCADE,
  UNIQUE(ename, maptype)
);

CREATE TABLE IF NOT EXISTS attribute(
  ename, maptype TEXT,
  FOREIGN KEY(ename) REFERENCES mapitem(ename)
  ON DELETE CASCADE ON UPDATE CASCADE,
  UNIQUE(ename, maptype)
);

CREATE TABLE IF NOT EXISTS object(
  ename, objtype TEXT, jsonval TEXT,
  FOREIGN KEY(ename) REFERENCES mapitem(ename)
  ON DELETE CASCADE ON UPDATE CASCADE,
  CHECK (objtype IN (
  	'point', 'multipoint', 'linestring',
		 'multilinestring', 'polygon', 'multipolygon')),
  UNIQUE(ename, objtype, jsonval)
);