1 files changed, 126 insertions, 0 deletions
diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
new file mode 100644
index 00000000000..fb40a85fd91
--- /dev/null
+++ b/sql/sql_derived.cc
@@ -0,0 +1,126 @@
+/* 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 */
+
+
+/*
+  Derived tables
+  These were introduced by Monty and Sinisa <sinisa@mysql.com>
+*/
+
+
+#include "mysql_priv.h"
+#include "sql_select.h"
+#include "sql_acl.h"
+
+static const char *any_db="*any*";	// Special symbol for check_access
+
+
+int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit, TABLE_LIST *t)
+{
+  /*
+    TODO: make derived tables with union inside (now only 1 SELECT may be
+    procesed)
+  */
+  SELECT_LEX *sl= unit->first_select();
+  List<Item> item_list;
+  TABLE *table;
+  int res;
+  select_union *derived_result;
+  TABLE_LIST *tables= (TABLE_LIST *)sl->table_list.first;
+  TMP_TABLE_PARAM tmp_table_param;
+  DBUG_ENTER("mysql_derived");
+  
+  if (tables)
+    res= check_table_access(thd,SELECT_ACL, tables);
+  else
+    res= check_access(thd, SELECT_ACL, any_db);
+  if (res)
+    DBUG_RETURN(-1);
+
+  for (TABLE_LIST *cursor= (TABLE_LIST *)tables;
+       cursor;
+       cursor=cursor->next)
+  {
+    if (cursor->derived)
+    {
+      res=mysql_derived(thd, lex, (SELECT_LEX_UNIT *)cursor->derived, cursor);
+      if (res) DBUG_RETURN(res);
+    }
+  }
+  Item *item;
+  List_iterator<Item> it(sl->item_list);
+
+  while ((item= it++))
+    item_list.push_back(item);
+    
+  if (!(res=open_and_lock_tables(thd,tables)))
+  {
+    if (tables && setup_fields(thd,tables,item_list,0,0,1))
+    {
+      res=-1;
+      goto exit;
+    }
+    bzero((char*) &tmp_table_param,sizeof(tmp_table_param));
+    tmp_table_param.field_count=item_list.elements;
+    if (!(table=create_tmp_table(thd, &tmp_table_param, item_list,
+			         (ORDER*) 0, 0, 1, 0,
+			         (sl->options | thd->options |
+				  TMP_TABLE_ALL_COLUMNS),
+                                 unit)))
+    {
+      res=-1;
+      goto exit;
+    }
+  
+    if ((derived_result=new select_union(table)))
+    {
+      unit->offset_limit_cnt= sl->offset_limit;
+      unit->select_limit_cnt= sl->select_limit+sl->offset_limit;
+      if (unit->select_limit_cnt < sl->select_limit)
+	unit->select_limit_cnt= HA_POS_ERROR;
+      if (unit->select_limit_cnt == HA_POS_ERROR)
+	sl->options&= ~OPTION_FOUND_ROWS;
+    
+      res=mysql_select(thd, tables,  sl->item_list,
+		       sl->where, (ORDER *) sl->order_list.first,
+		       (ORDER*) sl->group_list.first,
+		       sl->having, (ORDER*) NULL,
+		       sl->options | thd->options | SELECT_NO_UNLOCK,
+		       derived_result, unit);
+      if (!res)
+      {
+// Here we entirely fix both TABLE_LIST and list of SELECT's as there were no derived tables
+	if (derived_result->flush())
+	  res=1;
+	else
+	{
+	  t->real_name=table->real_name;
+	  t->table=table;
+	  sl->exclude();
+	  t->derived=(SELECT_LEX *)0; // just in case ...
+	}
+      }
+      delete derived_result;
+    }
+    if (res)
+      free_tmp_table(thd,table);
+exit:
+    close_thread_tables(thd);
+    if (res > 0)
+      send_error(&thd->net, ER_UNKNOWN_COM_ERROR); // temporary only ...
+  }
+  DBUG_RETURN(res);
+}