text: -- original: walnoshm.test
  -- credit:   http://www.sqlite.org/src/tree?ci=trunk&name=test
  
  CREATE TABLE t1(x, y);
    INSERT INTO t1 VALUES(1, 2)
  ;PRAGMA journal_mode = WAL;
    SELECT * FROM t1
  ;PRAGMA locking_mode = exclusive;
    PRAGMA journal_mode = WAL;
    SELECT * FROM t1
  ;INSERT INTO t1 VALUES(3, 4)
  ;PRAGMA locking_mode = normal
  ;PRAGMA journal_mode = delete;
    PRAGMA main.locking_mode
  ;PRAGMA locking_mode = normal
  ;SELECT * FROM t1
  ;CREATE TABLE t2(x, y);
    INSERT INTO t2 VALUES('a', 'b');
    INSERT INTO t2 VALUES('c', 'd')
  ;PRAGMA locking_mode = exclusive;
    PRAGMA journal_mode = WAL;
    INSERT INTO t2 VALUES('e', 'f');
    INSERT INTO t2 VALUES('g', 'h')
  ;PRAGMA locking_mode = exclusive; 
      PRAGMA journal_mode = delete;
      SELECT * FROM t2
  ;SELECT * FROM t2
  ;PRAGMA locking_mode = exclusive
  ;SELECT * FROM t2
  ;SELECT * FROM t2
  ;SELECT * FROM t2
  ;SELECT * FROM t1;
      PRAGMA locking_mode = EXCLUSIVE;
      INSERT INTO t1 VALUES(5, 6);
      PRAGMA locking_mode = NORMAL;
      INSERT INTO t1 VALUES(7, 8)
  ;SELECT * FROM t1
  ;PRAGMA locking_mode = EXCLUSIVE;
      INSERT INTO t1 VALUES(9, 10);
      PRAGMA locking_mode = NORMAL;
      INSERT INTO t1 VALUES(11, 12);