Fix UNION

New faster list iterators
Change list code to be simpler and faster
Optimize count(distinct)
New error messages for UNION
Make create_tmp_table more general to be usable by UNION


Docs/manual.texi:
  Changelog
include/mysqld_error.h:
  Add new error messages needed for UNION
mysql-test/r/union.result:
  New tests for UNION
mysql-test/t/analyse.test:
  Add missing drop table
mysql-test/t/union.test:
  new tests for UNION
sql/Makefile.am:
  Change name of sql_unions.cc to sql_union.cc
sql/item.cc:
  Use List_iterator_fast
sql/item_cmpfunc.cc:
  Use List_iterator_fast
sql/item_func.cc:
  Use List_iterator_fast
sql/item_sum.cc:
  Use List_iterator_fast
  Optimize count(distinct)
  Cleanup of indentation and comments
sql/item_sum.h:
  Optimize count(distinct)
sql/key.cc:
  Use List_iterator_fast
sql/mysql_priv.h:
  Add new option bits
sql/opt_sum.cc:
  Use List_iterator_fast
sql/share/Makefile.am:
  Add 'fix_errors' label
sql/share/czech/errmsg.txt:
  Add new error messages needed for UNION
sql/share/danish/errmsg.txt:
  Add new error messages needed for UNION
sql/share/dutch/errmsg.txt:
  Add new error messages needed for UNION
sql/share/english/errmsg.txt:
  Add new error messages needed for UNION
sql/share/estonian/errmsg.txt:
  Add new error messages needed for UNION
sql/share/french/errmsg.txt:
  Add new error messages needed for UNION
sql/share/german/errmsg.txt:
  Add new error messages needed for UNION
sql/share/greek/errmsg.txt:
  Add new error messages needed for UNION
sql/share/hungarian/errmsg.txt:
  Add new error messages needed for UNION
sql/share/italian/errmsg.txt:
  Add new error messages needed for UNION
sql/share/japanese/errmsg.txt:
  Add new error messages needed for UNION
sql/share/korean/errmsg.txt:
  Add new error messages needed for UNION
sql/share/norwegian-ny/errmsg.txt:
  Add new error messages needed for UNION
sql/share/norwegian/errmsg.txt:
  Add new error messages needed for UNION
sql/share/polish/errmsg.txt:
  Add new error messages needed for UNION
sql/share/portuguese/errmsg.txt:
  Add new error messages needed for UNION
sql/share/romanian/errmsg.txt:
  Add new error messages needed for UNION
sql/share/russian/errmsg.txt:
  Add new error messages needed for UNION
sql/share/slovak/errmsg.txt:
  Add new error messages needed for UNION
sql/share/spanish/errmsg.txt:
  Add new error messages needed for UNION
sql/share/swedish/errmsg.txt:
  Add new error messages needed for UNION
sql/sql_analyse.cc:
  Use List_iterator_fast
sql/sql_base.cc:
  Use List_iterator_fast
  Add new argument to setup_fields
sql/sql_class.cc:
  Use List_iterator_fast
sql/sql_class.h:
  Create new class for UNION
sql/sql_handler.cc:
  Use List_iterator_fast
sql/sql_insert.cc:
  Use List_iterator_fast
sql/sql_lex.h:
  Cleanup
sql/sql_list.cc:
  Faster iteration of lists
sql/sql_list.h:
  Faster iterations of lists
sql/sql_load.cc:
  Use List_iterator_fast
sql/sql_parse.cc:
  Fix UNION code
sql/sql_select.cc:
  Use List_iterator_fast
  Make create_tmp_table more general to be usable by UNION
sql/sql_select.h:
  Changes to speed up copy_fields()
sql/sql_show.cc:
  Use List_iterator_fast
sql/sql_table.cc:
  Use List_iterator_fast
sql/sql_union.cc:
  Fix UNION code
sql/sql_update.cc:
  Use List_iterator_fast
sql/sql_yacc.yy:
  Fix UNION code

1 files changed, 217 insertions, 0 deletions

diff --git a/sql/sql_union.cc b/sql/sql_union.cc
new file mode 100644
index 00000000000..a06c8f87cf0
--- /dev/null
+++ b/sql/sql_union.cc
@@ -0,0 +1,217 @@
+/* Copyright (C) 2000 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+
+/*
+  UNION  of select's
+  UNION's  were introduced by Monty and Sinisa <sinisa@mysql.com>
+*/
+
+
+#include "mysql_priv.h"
+#include "sql_select.h"
+
+
+int mysql_union(THD *thd, LEX *lex)
+{
+  SELECT_LEX *sl, *last_sl;
+  ORDER *order;
+  List<Item> item_list;
+/*  TABLE_LIST *s=(TABLE_LIST*) lex->select_lex.table_list.first; */
+  TABLE *table;
+  TABLE_LIST *first_table, result_table_list;
+  TMP_TABLE_PARAM tmp_table_param;
+  select_result *result;
+  select_union *union_result;
+  int res;
+  uint elements;
+  DBUG_ENTER("mysql_union");
+
+  /* Find last select part as it's here ORDER BY and GROUP BY is stored */
+  elements= lex->select_lex.item_list.elements;
+  for (last_sl= &lex->select_lex;
+       last_sl->next;
+       last_sl=last_sl->next)
+  {
+    if (elements != last_sl->next->item_list.elements)
+    {
+      my_error(ER_WRONG_NUMBER_OF_COLUMNS_IN_SELECT,MYF(0));
+      return -1;
+    }
+  }
+
+  order = (ORDER *) last_sl->order_list.first;
+  {
+    Item *item;
+    List_iterator<Item> it(lex->select_lex.item_list);
+
+    /* Create a list of items that will be in the result set */
+    first_table= (TABLE_LIST*) lex->select_lex.table_list.first;
+    while ((item= it++))
+      if (item_list.push_back(item))
+	DBUG_RETURN(-1);
+    if (setup_fields(thd,first_table,item_list,0,0,1))
+      DBUG_RETURN(-1);
+  }
+  bzero((char*) &tmp_table_param,sizeof(tmp_table_param));
+  tmp_table_param.field_count=elements;
+  if (!(table=create_tmp_table(thd, &tmp_table_param, item_list,
+			       (ORDER*) 0, !lex->union_option,
+			       1, 0,
+			       (lex->select_lex.options | thd->options |
+				TMP_TABLE_ALL_COLUMNS))))
+    DBUG_RETURN(-1);
+  table->file->extra(HA_EXTRA_WRITE_CACHE);
+  table->file->extra(HA_EXTRA_IGNORE_DUP_KEY);
+  bzero((char*) &result_table_list,sizeof(result_table_list));
+  result_table_list.db= (char*) "";
+  result_table_list.real_name=result_table_list.name=(char*) "union";
+  result_table_list.table=table;
+
+  if (!(union_result=new select_union(table)))
+  {
+    res= -1;
+    goto exit;
+  }
+  for (sl= &lex->select_lex; sl; sl=sl->next)
+  {
+    thd->offset_limit=sl->offset_limit;
+    thd->select_limit=sl->select_limit+sl->offset_limit;
+    if (thd->select_limit < sl->select_limit)
+      thd->select_limit= HA_POS_ERROR;		// no limit
+    if (thd->select_limit == HA_POS_ERROR)
+      sl->options&= ~OPTION_FOUND_ROWS;
+
+    res=mysql_select(thd,(TABLE_LIST*) sl->table_list.first,
+		     sl->item_list,
+		     sl->where,
+		     sl->ftfunc_list,
+		     (ORDER*) 0,
+		     (ORDER*) sl->group_list.first,
+		     sl->having,
+		     (ORDER*) NULL,
+		     sl->options | thd->options | SELECT_NO_UNLOCK,
+		     union_result);
+    if (res)
+      goto exit;
+  }
+  if (union_result->flush())
+  {
+    res= 1;					// Error is already sent
+    goto exit;
+  }
+  delete union_result;
+
+  /*
+    Sinisa, we must also be able to handle
+    CREATE TABLE ... and INSERT ... SELECT with unions
+
+    To do this, it's probably best that we add a new handle_select() function
+    which takes 'select_result' as parameter and let this internally handle
+    SELECT with and without unions.
+  */
+
+  if (lex->exchange)
+  {
+    if (lex->exchange->dumpfile)
+      result=new select_dump(lex->exchange);
+    else
+      result=new select_export(lex->exchange);
+  }
+  else
+    result=new select_send();
+  res =-1;
+  if (result)
+  {
+    /* Create a list of fields in the temporary table */
+    List_iterator<Item> it(item_list);
+    Field **field;
+    List<Item_func_match> ftfunc_list;
+    ftfunc_list.empty();
+
+    for (field=table->field ; *field ; field++)
+    {
+      (void) it++;
+      (void) it.replace(new Item_field(*field));
+    }
+    if (!thd->fatal_error)			// Check if EOM
+      res=mysql_select(thd,&result_table_list,
+		       item_list, NULL, ftfunc_list, order,
+		       (ORDER*) NULL, NULL, (ORDER*) NULL,
+		       thd->options, result);
+    if (res)
+      result->abort();
+    delete result;
+  }
+
+exit:
+  free_tmp_table(thd,table);
+  DBUG_RETURN(res);
+}
+
+
+/***************************************************************************
+** store records in temporary table for UNION
+***************************************************************************/
+
+select_union::select_union(TABLE *table_par)
+    :table(table_par)
+{
+  bzero((char*) &info,sizeof(info));
+  /*
+    We can always use DUP_IGNORE because the temporary table will only
+    contain a unique key if we are using not using UNION ALL
+  */
+  info.handle_duplicates=DUP_IGNORE;
+}
+
+select_union::~select_union()
+{
+}
+
+int select_union::prepare(List<Item> &list)
+{
+  return 0;
+}
+
+bool select_union::send_data(List<Item> &values)
+{
+  if (thd->offset_limit)
+  {						// using limit offset,count
+    thd->offset_limit--;
+    return 0;
+  }
+  fill_record(table->field,values);
+  return write_record(table,&info) ? 1 : 0;
+}
+
+bool select_union::send_eof()
+{
+  return 0;
+}
+
+bool select_union::flush()
+{
+  int error,error2;
+  error=table->file->extra(HA_EXTRA_NO_CACHE);
+  if (error)
+  {
+    table->file->print_error(error,MYF(0));
+    ::send_error(&thd->net);
+    return 1;
+  }
+  return 0;
+}