SQLite

    }

    sqlite3_free(zSql);
    sqlite3_free(zCols);
    *pRc = rc;
  }
}

/*
** Create the %_stat table if it does not already exist.
*/
void sqlite3Fts3CreateStatTable(int *pRc, Fts3Table *p){
  fts3DbExec(pRc, p->db, 
      "CREATE TABLE IF NOT EXISTS %Q.'%q_stat'"
          "(id INTEGER PRIMARY KEY, value BLOB);",
      p->zDb, p->zName
  );
  if( (*pRc)==SQLITE_OK ) p->bHasStat = 1;
}

/*
** Create the backing store tables (%_content, %_segments and %_segdir)
** required by the FTS3 table passed as the only argument. This is done
** as part of the vtab xCreate() method.
**
** If the p->bHasDocsize boolean is true (indicating that this is an

  if( p->bHasDocsize ){
    fts3DbExec(&rc, db, 
        "CREATE TABLE %Q.'%q_docsize'(docid INTEGER PRIMARY KEY, size BLOB);",
        p->zDb, p->zName
    );
  }
  if( p->bHasStat ){
    sqlite3Fts3CreateStatTable(&rc, p);



  }
  return rc;
}

/*
** Store the current database page-size in bytes in p->nPgsz.
**

  /* If this is an xCreate call, create the underlying tables in the 
  ** database. TODO: For xConnect(), it could verify that said tables exist.
  */
  if( isCreate ){
    rc = fts3CreateTables(p);
  }

  /* Check to see if a legacy fts3 table has been "upgraded" by the
  ** addition of a %_stat table so that it can use incremental merge.
  */
  if( !isFts4 && !isCreate ){
    int rc2 = SQLITE_OK;
    fts3DbExec(&rc2, db, "SELECT 1 FROM %Q.'%q_stat' WHERE id=2",
               p->zDb, p->zName);
    if( rc2==SQLITE_OK ) p->bHasStat = 1;
  }

  /* Figure out the page-size for the database. This is required in order to
  ** estimate the cost of loading large doclists from the database.  */
  fts3DatabasePageSize(&rc, p);
  p->nNodeSize = p->nPgsz-35;

  /* Declare the table schema to SQLite. */

int sqlite3Fts3GetVarint(const char *, sqlite_int64 *);
int sqlite3Fts3GetVarint32(const char *, int *);
int sqlite3Fts3VarintLen(sqlite3_uint64);
void sqlite3Fts3Dequote(char *);
void sqlite3Fts3DoclistPrev(int,char*,int,char**,sqlite3_int64*,int*,u8*);
int sqlite3Fts3EvalPhraseStats(Fts3Cursor *, Fts3Expr *, u32 *);
int sqlite3Fts3FirstFilter(sqlite3_int64, char *, int, char *);
void sqlite3Fts3CreateStatTable(int*, Fts3Table*);

/* fts3_tokenizer.c */
const char *sqlite3Fts3NextToken(const char *, int *);
int sqlite3Fts3InitHashTable(sqlite3 *, Fts3Hash *, const char *);
int sqlite3Fts3InitTokenizer(Fts3Hash *pHash, const char *, 
    sqlite3_tokenizer **, char **
);

    z++;
    nMin = fts3Getint(&z);
  }

  if( z[0]!='\0' || nMin<2 ){
    rc = SQLITE_ERROR;
  }else{
    rc = SQLITE_OK;
    if( !p->bHasStat ) sqlite3Fts3CreateStatTable(&rc, p);
    if( rc==SQLITE_OK ){
      rc = sqlite3Fts3Incrmerge(p, nMerge, nMin);
    }
    sqlite3Fts3SegmentsClose(p);
  }
  return rc;
}

/*
** Process statements of the form:
**
**    INSERT INTO table(table) VALUES('automerge=X');
**
** where X is an integer.  X==0 means to turn automerge off.  X!=0 means
** turn it on.  The setting is persistent.
*/
static int fts3DoAutoincrmerge(
  Fts3Table *p,                   /* FTS3 table handle */
  const char *zParam              /* Nul-terminated string containing boolean */
){
  int rc = SQLITE_OK;
  sqlite3_stmt *pStmt = 0;
  p->bAutoincrmerge = fts3Getint(&zParam)!=0;
  if( !p->bHasStat ){
    sqlite3Fts3CreateStatTable(&rc, p);
    if( rc ) return rc;
  }
  rc = fts3SqlStmt(p, SQL_REPLACE_STAT, &pStmt, 0);
  if( rc ) return rc;;
  sqlite3_bind_int(pStmt, 1, FTS_STAT_AUTOINCRMERGE);
  sqlite3_bind_int(pStmt, 2, p->bAutoincrmerge);
  sqlite3_step(pStmt);
  rc = sqlite3_reset(pStmt);
  return rc;

# 2012 March 06
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing the incremental merge function.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/fts3_common.tcl
set ::testprefix fts3merge

# If SQLITE_ENABLE_FTS3 is defined, omit this file.
ifcapable !fts3 {
  finish_test
  return
}

#-------------------------------------------------------------------------
# Test cases 1.*
#
do_test 1.0 { fts3_build_db_1 1004 } {}
do_test 1.1 { fts3_integrity_check t1 } {ok}
do_execsql_test 1.1 { 
  SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level 
} {
  0 {0 1 2 3 4 5 6 7 8 9 10 11} 
  1 {0 1 2 3 4 5 6 7 8 9 10 11 12 13}
  2 {0 1 2}
}

for {set i 0} {$i<20} {incr i} {
  do_execsql_test 1.2.$i.1 { INSERT INTO t1(t1) VALUES('merge=1') }
  do_test 1.2.$i.2 { fts3_integrity_check t1 } ok
  do_execsql_test 1.2.$i.3 { 
    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 
} {
  0 {0 1 2 3} 
  1 {0 1 2 3 4 5 6} 
  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 
} {
  2 {0 1}
  3 0
}

#-------------------------------------------------------------------------
# Test cases 2.* test that errors in the xxx part of the 'merge=xxx' are
# handled correctly.
#
do_execsql_test 2.0 { CREATE VIRTUAL TABLE t2 USING fts3 }

foreach {tn arg} {
  1   {merge=abc}
  2   {merge=%%%}
  3   {merge=,}
  4   {merge=5,}
  5   {merge=6,%}
  6   {merge=6,six}
  7   {merge=6,1}
  8   {merge=6,0}
} {
  do_catchsql_test 2.$tn { 
    INSERT INTO t2(t2) VALUES($arg);
  } {1 {SQL logic error or missing database}}
}

#-------------------------------------------------------------------------
# Test cases 3.*
#
do_test 3.0 { 
  reset_db
  execsql { PRAGMA page_size = 512 }
  fts3_build_db_2 30040 
} {}
do_test 3.1 { fts3_integrity_check t2 } {ok}

do_execsql_test 3.2 { 
  SELECT level, group_concat(idx, ' ') FROM t2_segdir GROUP BY level 
} {
  0 {0 1 2 3 4 5 6} 
  1 {0 1 2 3 4} 
  2 {0 1 2 3 4} 
  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 
} {
  0 0 
  2 0
  3 0 
  4 0
  6 0
}

#-------------------------------------------------------------------------
# Test cases 4.*
#
reset_db
do_execsql_test 4.1 {
  PRAGMA page_size = 512;
  CREATE VIRTUAL TABLE t4 USING fts3;
  PRAGMA main.page_size;
} {512}

do_test 4.2 {
  foreach x {a c b d e f g h i j k l m n o p} {
    execsql "INSERT INTO t4 VALUES('[string repeat $x 600]')"
  }
  execsql {SELECT level, group_concat(idx, ' ') FROM t4_segdir GROUP BY level}
} {0 {0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15}}

foreach {tn expect} {
  1  "0 {0 1 2 3 4 5 6 7 8 9 10 11 12 13} 1 0"
  2  "0 {0 1 2 3 4 5 6 7 8 9 10 11 12}    1 0"
  3  "0 {0 1 2 3 4 5 6 7 8 9 10 11}       1 0"
  4  "0 {0 1 2 3 4 5 6 7 8 9 10}          1 0"
  5  "0 {0 1 2 3 4 5 6 7 8 9}             1 0"
  6  "0 {0 1 2 3 4 5 6 7 8}               1 0"
  7  "0 {0 1 2 3 4 5 6 7}                 1 0"
  8  "0 {0 1 2 3 4 5 6}                   1 0"
  9  "0 {0 1 2 3 4 5}                     1 0"
} {
  do_execsql_test 4.3.$tn {
    INSERT INTO t4(t4) VALUES('merge=1,16');
    SELECT level, group_concat(idx, ' ') FROM t4_segdir GROUP BY level;
  } $expect
}

do_execsql_test 4.4.1 {
  SELECT quote(value) FROM t4_stat WHERE rowid=1
} {X'0006'}

do_execsql_test 4.4.2 {
  DELETE FROM t4_stat WHERE rowid=1;
  INSERT INTO t4(t4) VALUES('merge=1,12');
  SELECT level, group_concat(idx, ' ') FROM t4_segdir GROUP BY level;
} "0 {0 1 2 3 4 5}                     1 0"


#-------------------------------------------------------------------------
# Test cases 5.*
#
# Test that if a crisis-merge occurs that disrupts an ongoing incremental
# merge, the next call to "merge=A,B" identifies this and starts a new
# incremental merge. There are two scenarios:
#
#   * There are less segments on the input level that the disrupted
#     incremental merge operated on, or
#   
#   * Sufficient segments exist on the input level but the segments 
#     contain keys smaller than the largest key in the potential output 
#     segment.
# 
do_test 5.1 {
  reset_db
  fts3_build_db_1 1000
} {}

do_execsql_test 5.2 {
  SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
} {
  0 {0 1 2 3 4 5 6 7} 
  1 {0 1 2 3 4 5 6 7 8 9 10 11 12 13} 
  2 {0 1 2}
}

do_execsql_test 5.3 {
  INSERT INTO t1(t1) VALUES('merge=1,4');
  SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
} {
  0 {0 1 2 3 4 5 6 7} 
  1 {0 1 2 3 4 5 6 7 8 9 10 11 12 13} 
  2 {0 1 2 3}
}

do_execsql_test 5.4 {SELECT quote(value) from t1_stat WHERE rowid=1} {X'0104'}
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'0104'}

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 8 9 10 11 12 13 14 15} 
  1 {0 1 2 3 4 5 6 7 8 9 10 11} 
  2 {0 1 2 3 4 5 6 7}
  X'0104'
}

do_execsql_test 5.8 {
  INSERT INTO t1(t1) VALUES('merge=1,4');
  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 12 13 14 15} 
  1 {0 1 2 3 4 5 6 7 8 9 10 11} 
  2 {0 1 2 3 4 5 6 7}
  3 {0}
  X'0204'
}

do_test 5.9 {
  set L [expr 16*16*8 + 16*4 + 1]
  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 0   2 0   3 {0 1}
  X'0204'
}

do_execsql_test 5.11 {
  INSERT INTO t1(t1) VALUES('merge=10,4');
  SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level;
  SELECT quote(value) from t1_stat WHERE rowid=1;
} {
  0 0   1 0   2 0   3 {0 1}
  X'0000'
}

#-------------------------------------------------------------------------
# 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
# segment, which was unexpected).
#
do_test 6.1 {
  reset_db
  set a [string repeat a 900]
  set b [string repeat b 900]
  set c [string repeat c 900]
  set d [string repeat d 900]
  execsql {
    CREATE VIRTUAL TABLE t1 USING fts3;
    BEGIN;
      INSERT INTO t1 VALUES($a);
      INSERT INTO t1 VALUES($b);
    COMMIT;
    BEGIN;
      INSERT INTO t1 VALUES($c);
      INSERT INTO t1 VALUES($d);
    COMMIT;
  }

  execsql {
    INSERT INTO t1(t1) VALUES('merge=1,2');
    INSERT INTO t1(t1) VALUES('merge=1,2');
  }
} {}

#-------------------------------------------------------------------------
# Test cases 7.*
#
# Test that the value returned by sqlite3_total_changes() increases by
# 1 following a no-op "merge=A,B", or by more than 1 if actual work is
# performed.
#
do_test 7.0 {
  reset_db
  fts3_build_db_1 1000
} {}

do_execsql_test 7.1 {
  SELECT level, group_concat(idx, ' ') FROM t1_segdir GROUP BY level
} {
  0 {0 1 2 3 4 5 6 7} 
  1 {0 1 2 3 4 5 6 7 8 9 10 11 12 13} 
  2 {0 1 2}
}
do_test 7.2 {
  set x [db total_changes]
  execsql { INSERT INTO t1(t1) VALUES('merge=2,10') }
  expr { ([db total_changes] - $x)>1 }
} {1}
do_test 7.3 {
  set x [db total_changes]
  execsql { INSERT INTO t1(t1) VALUES('merge=200,10') }
  expr { ([db total_changes] - $x)>1 }
} {1}
do_test 7.4 {
  set x [db total_changes]
  execsql { INSERT INTO t1(t1) VALUES('merge=200,10') }
  expr { ([db total_changes] - $x)>1 }
} {0}
do_test 7.5 {
  set x [db total_changes]
  execsql { INSERT INTO t1(t1) VALUES('merge=200,10') }
  expr { ([db total_changes] - $x)>1 }
} {0}

finish_test