VdbeComment((v, "%s", pEList->a[i].zName));
    }
  }else if( eDest!=SRT_Exists ){
    /* If the destination is an EXISTS(...) expression, the actual
    ** values returned by the SELECT are not required.
    */
    sqlite3ExprCodeExprList(pParse, pEList, regResult,
                            (eDest==SRT_Output)?SQLITE_ECEL_DUP:0);
  }

  /* If the DISTINCT keyword was present on the SELECT statement
  ** and this row has been seen before, then do not make this row
  ** part of the result.
  */
  if( hasDistinct ){

      VdbeComment((v, "%s", pEList->a[i].zName));
    }
  }else if( eDest!=SRT_Exists ){
    /* If the destination is an EXISTS(...) expression, the actual
    ** values returned by the SELECT are not required.
    */
    sqlite3ExprCodeExprList(pParse, pEList, regResult,
                  (eDest==SRT_Output||eDest==SRT_Coroutine)?SQLITE_ECEL_DUP:0);
  }

  /* If the DISTINCT keyword was present on the SELECT statement
  ** and this row has been seen before, then do not make this row
  ** part of the result.
  */
  if( hasDistinct ){

# 2014-03-03
#
# 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 verifies that an OP_Copy operation is used instead of OP_SCopy
# in a compound select in a case where the source register might be changed
# before the copy is used.
#

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

do_execsql_test 1 {
  BEGIN TRANSACTION;
  CREATE TABLE t1(a, b, c);
  INSERT INTO "t1" VALUES(1,'one','I');
  CREATE TABLE t2(d, e, f);
  INSERT INTO "t2" VALUES(5,'ten','XX');
  INSERT INTO "t2" VALUES(6,NULL,NULL);

  CREATE INDEX i1 ON t1(b, a);
  COMMIT;
}

#explain_i {
#  SELECT * FROM t2
#  UNION ALL 
#  SELECT * FROM t1 WHERE a<5 
#  ORDER BY 2, 1
#}

do_execsql_test 2 {
  SELECT * FROM t2
  UNION ALL 
  SELECT * FROM t1 WHERE a<5 
  ORDER BY 2, 1
} {6 {} {} 1 one I 5 ten XX}


  
finish_test

  # Set up colors for the different opcodes. Scheme is as follows:
  #
  #   Red:   Opcodes that write to a b-tree.
  #   Blue:  Opcodes that reposition or seek a cursor. 
  #   Green: The ResultRow opcode.
  #

  set R "\033\[31;1m"        ;# Red fg
  set G "\033\[32;1m"        ;# Green fg
  set B "\033\[34;1m"        ;# Red fg
  set D "\033\[39;0m"        ;# Default fg






  foreach opcode {
      Seek SeekGe SeekGt SeekLe SeekLt NotFound Last Rewind
      NoConflict Next Prev VNext VPrev VFilter
  } {
    set color($opcode) $B
  }
  foreach opcode {ResultRow} {

  # Set up colors for the different opcodes. Scheme is as follows:
  #
  #   Red:   Opcodes that write to a b-tree.
  #   Blue:  Opcodes that reposition or seek a cursor. 
  #   Green: The ResultRow opcode.
  #
  if { [catch {fconfigure stdout -mode}]==0 } {
    set R "\033\[31;1m"        ;# Red fg
    set G "\033\[32;1m"        ;# Green fg
    set B "\033\[34;1m"        ;# Red fg
    set D "\033\[39;0m"        ;# Default fg
  } else {
    set R ""
    set G ""
    set B ""
    set D ""
  }
  foreach opcode {
      Seek SeekGe SeekGt SeekLe SeekLt NotFound Last Rewind
      NoConflict Next Prev VNext VPrev VFilter
  } {
    set color($opcode) $B
  }
  foreach opcode {ResultRow} {