SQLite

    ** nSeg to nMin. If no level with at least nMin segments can be found, 
    ** set nSeg to -1.
    */
    rc = fts3SqlStmt(p, SQL_FIND_MERGE_LEVEL, &pFindLevel, 0);
    sqlite3_bind_int(pFindLevel, 1, MAX(2, nMin));
    if( sqlite3_step(pFindLevel)==SQLITE_ROW ){
      iAbsLevel = sqlite3_column_int64(pFindLevel, 0);

      nSeg = sqlite3_column_int(pFindLevel, 1);

      assert( nSeg>=2 );

    }else{
      nSeg = -1;
    }
    rc = sqlite3_reset(pFindLevel);

    /* If the hint read from the %_stat table is not empty, check if the
    ** last entry in it specifies a relative level smaller than or equal

  /* If the first integer value is followed by a ',',  read the second
  ** integer value. */
  if( z[0]==',' && z[1]!='\0' ){
    z++;
    nMin = fts3Getint(&z);
  }

  if( z[0]!='\0' || nMin<2 ){
    rc = SQLITE_ERROR;
  }else{
    rc = SQLITE_OK;
    if( !p->bHasStat ){
      assert( p->bFts4==0 );
      sqlite3Fts3CreateStatTable(&rc, p);
    }

  code2 { sqlite3 db test.db }

  foreach c {code1 code2} {
    $c {
      set v [split [db version] .]
      if {[llength $v]==3} {lappend v 0}
      set ::sqlite_libversion [format \
        "%d%.2d%.2d%.2d" [lindex $v 0] [lindex $v 1] [lindex $v 2] [lindex $v 3]
      ]
    }
  }

  uplevel $script

  catch { code1 { db close } }

          SELECT level, group_concat(idx, ' ') FROM t2_segdir GROUP BY level;
        }
      } {0 {0 1 2 3 4 5}}

      if {[code1 { set ::sqlite_libversion }] >=3071200 
       && [code2 { set ::sqlite_libversion }] >=3071200 
      } {
        if {[code1 { set ::sqlite_libversion }]<3120000} {
          set res {0 {0 1} 1 0}
        } else {
          set res {1 0}
        }

        do_test backcompat-3.9 {
          sql1 { INSERT INTO t2(t2) VALUES('merge=100,4'); }
          sql2 { INSERT INTO t2(t2) VALUES('merge=100,4'); }
          sql1 { INSERT INTO t2(t2) VALUES('merge=100,4'); }
          sql2 { INSERT INTO t2(t2) VALUES('merge=2500,4'); }
          sql2 {
            SELECT level, group_concat(idx, ' ') FROM t2_segdir GROUP BY level;
          }
        } $res

        do_test backcompat-3.10 {
          sql1 { INSERT INTO t2(t2) VALUES('integrity-check') }
          sql2 { INSERT INTO t2(t2) VALUES('integrity-check') }
        } {}
      }
    }

  } {
    execsql { INSERT INTO x1 VALUES($L) }
  }
  execsql { 
    INSERT INTO x1(x1) VALUES('merge=4,4');
    SELECT level, end_block, length(root) FROM x1_segdir;
  }
} {1 {224 921} 2}

do_execsql_test 1.5 {
  SELECT length(block) FROM x1_segments;
} {921 {}}

do_test 1.6 {
  foreach L {
    {'Twas Mulga Bill, from Eaglehawk, that sought his own abode,}
    {That perched above Dead Man's Creek, beside the mountain road.}
    {He turned the cycle down the hill and mounted for the fray,}
    {But 'ere he'd gone a dozen yards it bolted clean away.}

    {It left the track, and through the trees, just like a silver steak,}
    {It whistled down the awful slope towards the Dead Man's Creek.}
    {It shaved a stump by half an inch, it dodged a big white-box:}
    {The very wallaroos in fright went scrambling up the rocks,}

    {The wombats hiding in their caves dug deeper underground,}
    {As Mulga Bill, as white as chalk, sat tight to every bound.}
    {It struck a stone and gave a spring that cleared a fallen tree,}
    {It raced beside a precipice as close as close could be;}

    {And then as Mulga Bill let out one last despairing shriek}
    {It made a leap of twenty feet into the Dead Man's Creek.}
    {It shaved a stump by half an inch, it dodged a big white-box:}
    {The very wallaroos in fright went scrambling up the rocks,}
    {The wombats hiding in their caves dug deeper underground,}
  } {
    execsql { INSERT INTO x1 VALUES($L) }
  }
  execsql { 
    SELECT level, end_block, length(root) FROM x1_segdir;
  }
} {1 {224 921} 2 1 {226 1230} 7 0 {0 98} 98}

do_execsql_test 1.7 {
  SELECT sum(length(block)) FROM x1_segments WHERE blockid IN (224,225,226)
} {1230}

#-------------------------------------------------------------------------
#
do_execsql_test 2.1 { 
  CREATE TABLE t1(docid, words);
  CREATE VIRTUAL TABLE x2 USING fts4;
}

do_execsql_test 2.5 { 
  SELECT end_block FROM x2_segdir WHERE level=3;
  INSERT INTO x2(x2) VALUES('merge=4,4');
  SELECT end_block FROM x2_segdir WHERE level=3;
  INSERT INTO x2(x2) VALUES('merge=4,4');
  SELECT end_block FROM x2_segdir WHERE level=3;
} {{5588 -3950} {5588 -11766} {5588 -15541}}

do_execsql_test 2.6 {
  SELECT sum(length(block)) FROM x2_segdir, x2_segments WHERE 
    blockid BETWEEN start_block AND leaves_end_block
    AND level=3
} {15541}

do_execsql_test 2.7 { 
  INSERT INTO x2(x2) VALUES('merge=1000,4');
  SELECT end_block FROM x2_segdir WHERE level=3;
} {{5588 127563}}

do_execsql_test 2.8 {
  SELECT sum(length(block)) FROM x2_segdir, x2_segments WHERE 
    blockid BETWEEN start_block AND leaves_end_block
    AND level=3
} {127563}

#--------------------------------------------------------------------------
# Test that delete markers are removed from FTS segments when possible.
# It is only possible to remove delete markers when the output of the
# merge operation will become the oldest segment in the index.
#
#   3.1 - when the oldest segment is created by an 'optimize'.

do_execsql_test 7.2 {
  INSERT INTO x6(x6) VALUES('merge=25,4');
  SELECT level, idx, end_block FROM x6_segdir;
} {
  0 0 {118 117483} 0 1 {238 118006} 0 2 {358 118006} 
  0 3 {478 118006} 0 4 {598 118006} 0 5 {718 118006}
  1 0 {23694 -69477}
}

do_execsql_test 7.3 {
  UPDATE x6_segdir SET end_block = first(end_block) WHERE level=1;
  SELECT level, idx, end_block FROM x6_segdir;
} {
  0 0 {118 117483} 0 1 {238 118006} 0 2 {358 118006} 
  0 3 {478 118006} 0 4 {598 118006} 0 5 {718 118006}
  1 0 23694
}

do_execsql_test 7.4 {
  INSERT INTO x6(x6) VALUES('merge=25,4');
  SELECT level, idx, end_block FROM x6_segdir;
} {
  0 0 {118 117483} 0 1 {238 118006} 0 2 {358 118006} 
  0 3 {478 118006} 0 4 {598 118006} 0 5 {718 118006}
  1 0 23694
}

do_execsql_test 7.5 {
  INSERT INTO x6(x6) VALUES('merge=2500,4');
  SELECT level, idx, start_block, leaves_end_block, end_block FROM x6_segdir;
} {
  1 0 719 1171 23694
}

do_execsql_test 7.6 {
  INSERT INTO x6(x6) VALUES('merge=2500,2');
  SELECT level, idx, start_block, leaves_end_block, end_block FROM x6_segdir;
} {
  1 0 719 1171 23694
}

do_execsql_test 7.7 {
  SELECT sum(length(block)) FROM x6_segments 

} {635247}



finish_test

    INSERT INTO t6(t6) VALUES('merge=100,3');
    SELECT docid FROM t6 WHERE t6 MATCH '"zero zero"' AND lid=$lid;
  } {1 2 5}

  do_execsql_test 5.4.$lid.5 {
    SELECT count(*) FROM t6_segdir;
    SELECT count(*) FROM t6_segments;
  } {1 2}
}
finish_test

      SELECT docid FROM t1 WHERE t1 MATCH 'zero one two three'
    } {123 132 213 231 312 321}
  }
  
  do_execsql_test 1.3 { 
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level 
  } {


    2 {0 1 2 3}
  }
  
  for {set i 0} {$i<100} {incr i} {
    do_execsql_test 1.4.$i { INSERT INTO t1(t1) VALUES('merge=1,4') }
    do_test 1.4.$i.2 { fts3_integrity_check t1 } ok
    do_execsql_test 1.4.$i.3 { 
      SELECT docid FROM t1 WHERE t1 MATCH 'zero one two three'
    } {123 132 213 231 312 321}
  }
  
  do_execsql_test 1.5 { 
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level 
  } {

    3 0
  }
  
  #-------------------------------------------------------------------------
  # Test cases 2.* test that errors in the xxx part of the 'merge=xxx' are
  # handled correctly.
  #

    3 {0 1 2 3 4 5 6}
  }
  
  do_execsql_test 3.3 { 
    INSERT INTO t2(t2) VALUES('merge=1000000,2');
    SELECT level, group_concat(idx, ' ') FROM t2_segdir GROUP BY level 
  } {



    4 0

  }
  
  #-------------------------------------------------------------------------
  # Test cases 4.*
  #
  reset_db
  do_execsql_test 4.1 "

  }
  
  do_execsql_test 5.3 {
    INSERT INTO t1(t1) VALUES('merge=1,5');
    INSERT INTO t1(t1) VALUES('merge=1,5');
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
  } {

    1 {0 1 2 3 4 5 6 7 8 9 10 11 12 13 14} 
    2 {0 1 2 3}
  }
  
  do_execsql_test 5.4 {SELECT quote(value) from t1_stat WHERE rowid=1} {X'010F'}
  do_test 5.5 {
    foreach docid [execsql {SELECT docid FROM t1}] {
      execsql {INSERT INTO t1 SELECT * FROM t1 WHERE docid=$docid}
    }
  } {}
  
  do_execsql_test 5.6 {SELECT quote(value) from t1_stat WHERE rowid=1} {X'010F'}
  
  do_execsql_test 5.7 {
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
    SELECT quote(value) from t1_stat WHERE rowid=1;
  } {
    0 {0 1 2 3 4 5 6 7} 
    1 {0 1 2 3 4 5 6 7 8 9 10 11 12} 
    2 {0 1 2 3 4 5 6 7} 
    X'010F'
  }
  
  do_execsql_test 5.8 {
    INSERT INTO t1(t1) VALUES('merge=1,6');
    INSERT INTO t1(t1) VALUES('merge=1,6');
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
    SELECT quote(value) from t1_stat WHERE rowid=1;
  } {

    1 {0 1 2 3 4 5 6 7 8 9 10 11 12 13} 
    2 {0 1 2 3 4 5 6 7 8} X'010E'
  }
  
  do_test 5.8.1 { fts3_integrity_check t1 } ok
  
  do_test 5.9 {
    set L [expr 16*16*7 + 16*3 + 12]
    foreach docid [execsql {
        SELECT docid FROM t1 UNION ALL SELECT docid FROM t1 LIMIT $L
    }] {
      execsql {INSERT INTO t1 SELECT * FROM t1 WHERE docid=$docid}
    }
  } {}
  
  do_execsql_test 5.10 {
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
    SELECT quote(value) from t1_stat WHERE rowid=1;
  } {
    0 {0 1 2 3 4 5 6 7 8 9 10 11} 1 0 2 0 3 0 X'010E'
  }
  
  do_execsql_test 5.11 {
    INSERT INTO t1(t1) VALUES('merge=1,6');
    SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
    SELECT quote(value) from t1_stat WHERE rowid=1;
  } {
    1 {0 1} 2 0 3 0 X'010E'
  }
  
  #-------------------------------------------------------------------------
  # Test cases 6.*
  #
  # At one point the following test caused an assert() to fail (because the
  # second 'merge=1,2' operation below actually "merges" a single input

      do_test 1.6.$i.2 { 
        sql2 "SELECT docid FROM t2 WHERE t2 MATCH 'abc'" 
      } {1485}
    }

    do_test 1.7 { sql2 { 
      SELECT level, count(*) FROM t2_segdir GROUP BY level ORDER BY 1
    } } {2 15 3 5}

    # Using the old connection, insert many rows. 
    do_test 1.8 {
      for {set i 0} {$i < 1500} {incr i} {
        sql2 "INSERT INTO t2 SELECT content FROM t2 WHERE docid = $i"
      }
    } {}

    do_test 1.9 { sql2 { 
      SELECT level, count(*) FROM t2_segdir GROUP BY level ORDER BY 1
    } } [list  0 12  1 13  2 4  3 6]

    # Run a big incr-merge operation on the db.
    do_test 1.10 { sql1 { INSERT INTO t2(t2) VALUES('merge=2000,2') } } {}
    do_test 1.11 { 
      sql2 "SELECT docid FROM t2 WHERE t2 MATCH 'abc'" 
    } {1485 21485}

    do_test 1.14 { 
      sql2 "INSERT INTO t2(t2) VALUES('optimize')"
      sql2 "SELECT docid FROM t2 WHERE t2 MATCH 'abc'" 
    } {1485 21485 22985}

    do_test 1.15 { sql2 { 
      SELECT level, count(*) FROM t2_segdir GROUP BY level ORDER BY 1
    } } {4 1}
  }
}


finish_test

  2080 33 
  3104 33
}

do_test 1.6 {
  while 1 {
    set tc1 [db total_changes]
    execsql { INSERT INTO t2(t2) VALUES('merge=5,2') }
    set tc2 [db total_changes]
    if {($tc2 - $tc1) < 2} break
  }
  execsql { SELECT level, count(*) FROM t2_segdir GROUP BY level }
} {33 1 1057 1 2081 1 3105 1}
do_execsql_test 1.7 { INSERT INTO t2(t2) VALUES('integrity-check') }

  2080 37 
  3104 37
}

do_test 2.6 {
  while 1 {
    set tc1 [db total_changes]
    execsql { INSERT INTO t2(t2) VALUES('merge=5,2') }
    set tc2 [db total_changes]
    if {($tc2 - $tc1) < 2} break
  }
  execsql { SELECT level, count(*) FROM t2_segdir GROUP BY level }
} {33 1 1057 1 2081 1 3105 1}
do_execsql_test 2.7 { INSERT INTO t2(t2) VALUES('integrity-check') }

do_execsql_test 2.8 {
  INSERT INTO t2(words) SELECT words FROM t1;
  SELECT level, count(*) FROM t2_segdir GROUP BY level;
} {0 2 1024 2 2048 2 3072 2}

finish_test