text: -- original: fts4merge4.test
  -- credit:   http://www.sqlite.org/src/tree?ci=trunk&name=test
  
  CREATE VIRTUAL TABLE t1 USING fts4
  ;INSERT INTO t1 VALUES('a b c d e f g h i j k l')
  ;INSERT INTO t1 VALUES('a b c d e f g h i j k l')
  ;INSERT INTO t1(t1) VALUES('merge=8,50');
      COMMIT
  ;CREATE VIRTUAL TABLE t1 USING fts4
  ;INSERT INTO t1 VALUES('a b c d e f g h i j k l')
  ;SELECT count(*) FROM t1_segdir
  ;INSERT INTO t1(t1) VALUES('optimize')
  ;SELECT count(*) FROM t1_segdir
  ;CREATE VIRTUAL TABLE t2 USING fts4
  ;DELETE FROM t2
  ;INSERT INTO t2(t2) VALUES(sub_am)
  ;BEGIN;
              INSERT INTO t2 VALUES(sub_doc);
              INSERT INTO t2 VALUES(sub_doc);
              INSERT INTO t2 VALUES(sub_doc);
              INSERT INTO t2 VALUES(sub_doc);
              INSERT INTO t2 VALUES(sub_doc);
            COMMIT
  ;SELECT level, count(*) FROM t2_segdir GROUP BY level;