SQLite

    const char *zText = (const char *)sqlite3_value_text(apVal[i]);
    if( zText ){
      int rc = fts3PendingTermsAdd(p, zText, i-2, &aSz[i-2]);
      if( rc!=SQLITE_OK ){
        return rc;
      }
    }
    aSz[p->nColumn] += sqlite3_value_bytes(apVal[i]);
  }
  return SQLITE_OK;
}

/*
** This function is called by the xUpdate() method for an INSERT operation.
** The apVal parameter is passed a copy of the apVal argument passed by

}

/*
** The first element in the apVal[] array is assumed to contain the docid
** (an integer) of a row about to be deleted. Remove all terms from the
** full-text index.
*/
static void fts3DeleteTerms( 
  int *pRC,               /* Result code */
  Fts3Table *p,           /* The FTS table to delete from */
  sqlite3_value **apVal,  /* apVal[] contains the docid to be deleted */
  u32 *aSz                /* Sizes of deleted document written here */
){
  int rc;
  sqlite3_stmt *pSelect;

        const char *zText = (const char *)sqlite3_column_text(pSelect, i);
        rc = fts3PendingTermsAdd(p, zText, -1, &aSz[i-1]);
        if( rc!=SQLITE_OK ){
          sqlite3_reset(pSelect);
          *pRC = rc;
          return;
        }
        aSz[p->nColumn] += sqlite3_column_bytes(pSelect, i);
      }
    }
    rc = sqlite3_reset(pSelect);
  }else{
    sqlite3_reset(pSelect);
  }
  *pRC = rc;

        sqlite3_int64 nDoc = 0;
        sqlite3_int64 nByte = 0;
        const char *a = sqlite3_column_blob(pStmt, 0);
        if( a ){
          const char *pEnd = &a[sqlite3_column_bytes(pStmt, 0)];
          a += sqlite3Fts3GetVarint(a, &nDoc);
          while( a<pEnd ){

            a += sqlite3Fts3GetVarint(a, &nByte);

          }
        }

        pCsr->nRowAvg = (((nByte / nDoc) + pgsz - 1) / pgsz);
      }
      rc = sqlite3_reset(pStmt);
      if( rc!=SQLITE_OK || pCsr->nRowAvg==0 ) return rc;

  sqlite3_bind_int64(pStmt, 1, p->iPrevDocid);
  sqlite3_bind_blob(pStmt, 2, pBlob, nBlob, sqlite3_free);
  sqlite3_step(pStmt);
  *pRC = sqlite3_reset(pStmt);
}

/*
** Record 0 of the %_stat table contains a blob consisting of N varints,
** where N is the number of user defined columns in the fts3 table plus
** two. If nCol is the number of user defined columns, then values of the 
** varints are set as follows:
**
**   Varint 0:       Total number of rows in the table.
**
**   Varint 1..nCol: For each column, the total number of tokens stored in
**                   the column for all rows of the table.
**
**   Varint 1+nCol:  The total size, in bytes, of all text values in all
**                   columns of all rows of the table.
**
*/
static void fts3UpdateDocTotals(
  int *pRC,                       /* The result code */
  Fts3Table *p,                   /* Table being updated */
  u32 *aSzIns,                    /* Size increases */
  u32 *aSzDel,                    /* Size decreases */
  int nChng                       /* Change in the number of documents */
){
  char *pBlob;             /* Storage for BLOB written into %_stat */
  int nBlob;               /* Size of BLOB written into %_stat */
  u32 *a;                  /* Array of integers that becomes the BLOB */
  sqlite3_stmt *pStmt;     /* Statement for reading and writing */
  int i;                   /* Loop counter */
  int rc;                  /* Result code from subfunctions */

  const int nStat = p->nColumn+2;

  if( *pRC ) return;
  a = sqlite3_malloc( (sizeof(u32)+10)*nStat );
  if( a==0 ){
    *pRC = SQLITE_NOMEM;
    return;
  }
  pBlob = (char*)&a[nStat];
  rc = fts3SqlStmt(p, SQL_SELECT_DOCTOTAL, &pStmt, 0);
  if( rc ){
    sqlite3_free(a);
    *pRC = rc;
    return;
  }
  if( sqlite3_step(pStmt)==SQLITE_ROW ){
    fts3DecodeIntArray(nStat, a,
         sqlite3_column_blob(pStmt, 0),
         sqlite3_column_bytes(pStmt, 0));
  }else{
    memset(a, 0, sizeof(u32)*(nStat) );
  }
  sqlite3_reset(pStmt);
  if( nChng<0 && a[0]<(u32)(-nChng) ){
    a[0] = 0;
  }else{
    a[0] += nChng;
  }
  for(i=0; i<p->nColumn+1; i++){
    u32 x = a[i+1];
    if( x+aSzIns[i] < aSzDel[i] ){
      x = 0;
    }else{
      x = x + aSzIns[i] - aSzDel[i];
    }
    a[i+1] = x;
  }
  fts3EncodeIntArray(nStat, a, pBlob, &nBlob);
  rc = fts3SqlStmt(p, SQL_REPLACE_DOCTOTAL, &pStmt, 0);
  if( rc ){
    sqlite3_free(a);
    *pRC = rc;
    return;
  }
  sqlite3_bind_blob(pStmt, 1, pBlob, nBlob, SQLITE_STATIC);

  u32 *aSzIns;                    /* Sizes of inserted documents */
  u32 *aSzDel;                    /* Sizes of deleted documents */
  int nChng = 0;                  /* Net change in number of documents */

  assert( p->pSegments==0 );

  /* Allocate space to hold the change in document sizes */
  aSzIns = sqlite3_malloc( sizeof(aSzIns[0])*(p->nColumn+1)*2 );
  if( aSzIns==0 ) return SQLITE_NOMEM;
  aSzDel = &aSzIns[p->nColumn+1];
  memset(aSzIns, 0, sizeof(aSzIns[0])*(p->nColumn+1)*2);

  /* If this is a DELETE or UPDATE operation, remove the old record. */
  if( sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
    int isEmpty = 0;
    rc = fts3IsEmpty(p, apVal, &isEmpty);
    if( rc==SQLITE_OK ){
      if( isEmpty ){

  "csjqxhgj zm jk jk duszemmzl zk xh zm jk zf"
  "urvysbnykk dzadnqzprr csjqxhgj mjpavjuhw ubwrfqnbjf nkaotm jk jk zm drir"
  "nvfasfh xh igju zm wluvgsw jk zm srwwnezqk ewle ovnq"
  "jk nvfasfh eh ktxdty urvysbnykk vgsld zm jk eh uenvbm"
  "orpfawpx pahlds jk uhzq hi zm zm zf jk dzadnqzprr"
  "srwwnezqk csjqxhgj rbwzuf nvfasfh jcpiwj xldlpy nvfasfh jk vgsld wjybxmieki"
}

proc add_empty_records {n} {
  execsql BEGIN
  for {set i 0} {$i < $n} {incr i} {
    execsql { INSERT INTO t1 VALUES('') }
  }
  execsql COMMIT
}


#set e [list]
#foreach d $data {set e [concat $e $d]}
#puts [lsort -unique $e]
#exit

set zero_long_doclists {

    execsql { CREATE VIRTUAL TABLE t1 USING FTS4 }
    foreach doc $data { execsql { INSERT INTO t1 VALUES($doc) } }
  }
  3 {
    set dmt_modes {0 1 2}
    execsql { CREATE VIRTUAL TABLE t1 USING FTS4 }
    foreach doc $data { execsql { INSERT INTO t1 VALUES($doc) } }
    add_empty_records 1000
    execsql $zero_long_doclists
  }
  4 {
    set dmt_modes 0
    execsql { CREATE VIRTUAL TABLE t1 USING FTS4 }
    foreach doc $data { execsql { INSERT INTO t1 VALUES($doc) } }
    add_empty_records 1000
    execsql "INSERT INTO t1(t1) VALUES('optimize')"
    execsql $zero_long_doclists
  }
} {

  execsql { DROP TABLE IF EXISTS t1 }
  eval $setup
  set ::testprefix fts3defer-2.$tn
  set DO_MALLOC_TEST 0

  do_execsql_test 0 { 
    SELECT count(*) FROM t1_segments WHERE length(block)>10000 
  } {2}

  do_select_test 1.1 {
    SELECT rowid FROM t1 WHERE t1 MATCH 'jk xnxhf'
  } {13 29 40 47 48 52 63 92}
  do_select_test 1.2 {
    SELECT rowid FROM t1 WHERE t1 MATCH 'jk eh'
  } {100}
if {$tn==3} breakpoint
  do_select_test 1.3 {
    SELECT rowid FROM t1 WHERE t1 MATCH 'jk ubwrfqnbjf'
  } {7 70 98}
  do_select_test 1.4 {
    SELECT rowid FROM t1 WHERE t1 MATCH 'duszemmzl jk'
  } {3 5 8 10 13 18 20 23 32 37 41 43 55 60 65 67 72 74 76 81 94 96 97}
  do_select_test 1.5 {