text: -- select7.test
  -- 
  -- execsql {
  --     CREATE TABLE x(id integer primary key, a TEXT NULL);
  --     INSERT INTO x (a) VALUES ('first');
  --     CREATE TABLE tempx(id integer primary key, a TEXT NULL);
  --     INSERT INTO tempx (a) VALUES ('t-first');
  --     CREATE VIEW tv1 AS SELECT x.id, tx.id FROM x JOIN tempx tx ON tx.id=x.id;
  --     CREATE VIEW tv1b AS SELECT x.id, tx.id FROM x JOIN tempx tx on tx.id=x.id;
  --     CREATE VIEW tv2 AS SELECT * FROM tv1 UNION SELECT * FROM tv1b;
  --     SELECT * FROM tv2;
  -- }
  CREATE TABLE x(id integer primary key, a TEXT NULL);
  INSERT INTO x (a) VALUES ('first');
  CREATE TABLE tempx(id integer primary key, a TEXT NULL);
  INSERT INTO tempx (a) VALUES ('t-first');
  CREATE VIEW tv1 AS SELECT x.id, tx.id FROM x JOIN tempx tx ON tx.id=x.id;
  CREATE VIEW tv1b AS SELECT x.id, tx.id FROM x JOIN tempx tx on tx.id=x.id;
  CREATE VIEW tv2 AS SELECT * FROM tv1 UNION SELECT * FROM tv1b;
  SELECT * FROM tv2;