** the index b-tree.  */
    endOfLoop = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
    topOfLoop = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);

    for(i=0; i<nCol; i++){

      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
      if( i==0 ){
#ifdef SQLITE_ENABLE_STAT2
        /* Check if the record that cursor iIdxCur points to contains a
        ** value that should be stored in the sqlite_stat2 table. If so,
        ** store it.  */
        int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
................................................................................
        sqlite3VdbeJumpHere(v, ne);
        sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
#endif

        /* Always record the very first row */
        sqlite3VdbeAddOp1(v, OP_IfNot, iMem+1);
      }



      sqlite3VdbeAddOp3(v, OP_Ne, regCol, 0, iMem+nCol+i+1);
      /**** TODO:  add collating sequence *****/

      sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
    }
    if( db->mallocFailed ){
      /* If a malloc failure has occurred, then the result of the expression 
      ** passed as the second argument to the call to sqlite3VdbeJumpHere() 
      ** below may be negative. Which causes an assert() to fail (or an
      ** out-of-bounds write if SQLITE_DEBUG is not defined).  */

    ** the index b-tree.  */
    endOfLoop = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
    topOfLoop = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);

    for(i=0; i<nCol; i++){
      CollSeq *pColl;
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
      if( i==0 ){
#ifdef SQLITE_ENABLE_STAT2
        /* Check if the record that cursor iIdxCur points to contains a
        ** value that should be stored in the sqlite_stat2 table. If so,
        ** store it.  */
        int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
................................................................................
        sqlite3VdbeJumpHere(v, ne);
        sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
#endif

        /* Always record the very first row */
        sqlite3VdbeAddOp1(v, OP_IfNot, iMem+1);
      }
      assert( pIdx->azColl!=0 );
      assert( pIdx->azColl[i]!=0 );
      pColl = sqlite3LocateCollSeq(pParse, pIdx->azColl[i]);
      sqlite3VdbeAddOp4(v, OP_Ne, regCol, 0, iMem+nCol+i+1,

                       (char*)pColl, P4_COLLSEQ);
      sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
    }
    if( db->mallocFailed ){
      /* If a malloc failure has occurred, then the result of the expression 
      ** passed as the second argument to the call to sqlite3VdbeJumpHere() 
      ** below may be negative. Which causes an assert() to fail (or an
      ** out-of-bounds write if SQLITE_DEBUG is not defined).  */

#***********************************************************************
#
# This file implements regression tests for SQLite library. This file 
# implements tests for ANALYZE to verify that multiple rows containing
# a NULL value count as distinct rows for the purposes of analyze 
# statistics.
#



set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_test analyze4-1.0 {
  db eval {
    CREATE TABLE t1(a,b);
................................................................................
    CREATE INDEX t1bcd ON t1(b,c,d);
    CREATE INDEX t1cdb ON t1(c,d,b);
    CREATE INDEX t1cbd ON t1(c,b,d);
    ANALYZE;
    SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx;
  }
} {t1a {128 1} t1b {128 128} t1bcd {128 128 4 2} t1cbd {128 4 4 2} t1cdb {128 4 2 2}}






























finish_test

#***********************************************************************
#
# This file implements regression tests for SQLite library. This file 
# implements tests for ANALYZE to verify that multiple rows containing
# a NULL value count as distinct rows for the purposes of analyze 
# statistics.
#
# Also include test cases for collating sequences on indices.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_test analyze4-1.0 {
  db eval {
    CREATE TABLE t1(a,b);
................................................................................
    CREATE INDEX t1bcd ON t1(b,c,d);
    CREATE INDEX t1cdb ON t1(c,d,b);
    CREATE INDEX t1cbd ON t1(c,b,d);
    ANALYZE;
    SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx;
  }
} {t1a {128 1} t1b {128 128} t1bcd {128 128 4 2} t1cbd {128 4 4 2} t1cdb {128 4 2 2}}

# Verify that collating sequences are taken into account when computing
# ANALYZE statistics.
#
do_test analyze4-2.0 {
  db eval {
    CREATE TABLE t2(
      x INTEGER PRIMARY KEY,
      a TEXT COLLATE nocase,
      b TEXT COLLATE rtrim,
      c TEXT COLLATE binary
    );
    CREATE INDEX t2a ON t2(a);
    CREATE INDEX t2b ON t2(b);
    CREATE INDEX t2c ON t2(c);
    CREATE INDEX t2c2 ON t2(c COLLATE nocase);
    CREATE INDEX t2c3 ON t2(c COLLATE rtrim);
    INSERT INTO t2 VALUES(1, 'abc', 'abc', 'abc');
    INSERT INTO t2 VALUES(2, 'abC', 'abC', 'abC');
    INSERT INTO t2 VALUES(3, 'abc ', 'abc ', 'abc ');
    INSERT INTO t2 VALUES(4, 'abC ', 'abC ', 'abC ');
    INSERT INTO t2 VALUES(5, 'aBc', 'aBc', 'aBc');
    INSERT INTO t2 VALUES(6, 'aBC', 'aBC', 'aBC');
    INSERT INTO t2 VALUES(7, 'aBc ', 'aBc ', 'aBc ');
    INSERT INTO t2 VALUES(8, 'aBC ', 'aBC ', 'aBC ');
    ANALYZE;
    SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t2' ORDER BY idx;
  }
} {t2a {8 4} t2b {8 2} t2c {8 1} t2c2 {8 4} t2c3 {8 2}}

finish_test