Merge ramayana.hindu.god:/home/tsmith/m/bk/51

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/51


client/mysqldump.c:
  Auto merged
configure.in:
  Auto merged
sql/field.cc:
  Auto merged
sql/filesort.cc:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_timefunc.cc:
  Auto merged
sql/log.cc:
  Auto merged
sql/repl_failsafe.cc:
  Auto merged
sql/set_var.cc:
  Auto merged
sql/sp.cc:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_class.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_show.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged
sql/item_sum.cc:
  Manual merge.

14 files changed, 201 insertions, 100 deletions

diff --git a/sql/field.cc b/sql/field.cc
index 16217e69de9..7c4f6c9ff5f 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -1308,7 +1308,8 @@ Field::Field(uchar *ptr_arg,uint32 length_arg,uchar *null_ptr_arg,
    field_name(field_name_arg),
    key_start(0), part_of_key(0), part_of_key_not_clustered(0),
    part_of_sortkey(0), unireg_check(unireg_check_arg),
-   field_length(length_arg), null_bit(null_bit_arg)
+   field_length(length_arg), null_bit(null_bit_arg), 
+   is_created_from_null_item(FALSE)
 {
   flags=null_ptr ? 0: NOT_NULL_FLAG;
   comment.str= (char*) "";
@@ -5633,6 +5634,13 @@ String *Field_date::val_str(String *val_buffer,
 }
 
 
+bool Field_date::get_time(MYSQL_TIME *ltime)
+{
+  bzero((char *)ltime, sizeof(MYSQL_TIME));
+  return 0;
+}
+
+
 int Field_date::cmp(const uchar *a_ptr, const uchar *b_ptr)
 {
   int32 a,b;
diff --git a/sql/field.h b/sql/field.h
index 9f76deb18bc..a6a1d8bfabc 100644
--- a/sql/field.h
+++ b/sql/field.h
@@ -90,6 +90,16 @@ public:
   uint32	flags;
   uint16        field_index;            // field number in fields array
   uchar		null_bit;		// Bit used to test null bit
+  /**
+     If true, this field was created in create_tmp_field_from_item from a NULL
+     value. This means that the type of the field is just a guess, and the type
+     may be freely coerced to another type.
+
+     @see create_tmp_field_from_item
+     @see Item_type_holder::get_real_type
+
+   */
+  bool is_created_from_null_item;
 
   Field(uchar *ptr_arg,uint32 length_arg,uchar *null_ptr_arg,
         uchar null_bit_arg, utype unireg_check_arg,
@@ -1240,6 +1250,7 @@ public:
   double val_real(void);
   longlong val_int(void);
   String *val_str(String*,String *);
+  bool get_time(MYSQL_TIME *ltime);
   bool send_binary(Protocol *protocol);
   int cmp(const uchar *,const uchar *);
   void sort_string(uchar *buff,uint length);
@@ -1258,6 +1269,10 @@ public:
     :Field_str(ptr_arg, 10, null_ptr_arg, null_bit_arg,
 	       unireg_check_arg, field_name_arg, cs)
     {}
+  Field_newdate(bool maybe_null_arg, const char *field_name_arg,
+                CHARSET_INFO *cs)
+    :Field_str((uchar*) 0,10, maybe_null_arg ? (uchar*) "": 0,0,
+               NONE, field_name_arg, cs) {}
   enum_field_types type() const { return MYSQL_TYPE_DATE;}
   enum_field_types real_type() const { return MYSQL_TYPE_NEWDATE; }
   enum ha_base_keytype key_type() const { return HA_KEYTYPE_UINT24; }
diff --git a/sql/filesort.cc b/sql/filesort.cc
index 61c8ca3b256..3783aa2a06a 100644
--- a/sql/filesort.cc
+++ b/sql/filesort.cc
@@ -41,7 +41,8 @@ if (my_b_write((file),(uchar*) (from),param->ref_length)) \
 
 static char **make_char_array(char **old_pos, register uint fields,
                               uint length, myf my_flag);
-static BUFFPEK *read_buffpek_from_file(IO_CACHE *buffer_file, uint count);
+static uchar *read_buffpek_from_file(IO_CACHE *buffer_file, uint count,
+                                     uchar *buf);
 static ha_rows find_all_keys(SORTPARAM *param,SQL_SELECT *select,
 			     uchar * *sort_keys, IO_CACHE *buffer_file,
 			     IO_CACHE *tempfile,IO_CACHE *indexfile);
@@ -246,9 +247,14 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
   }
   else
   {
-    if (!table_sort.buffpek && table_sort.buffpek_len < maxbuffer &&
-        !(table_sort.buffpek=
-          (uchar *) read_buffpek_from_file(&buffpek_pointers, maxbuffer)))
+    if (table_sort.buffpek && table_sort.buffpek_len < maxbuffer)
+    {
+      x_free(table_sort.buffpek);
+      table_sort.buffpek= 0;
+    }
+    if (!(table_sort.buffpek=
+          (uchar *) read_buffpek_from_file(&buffpek_pointers, maxbuffer,
+                                 table_sort.buffpek)))
       goto err;
     buffpek= (BUFFPEK *) table_sort.buffpek;
     table_sort.buffpek_len= maxbuffer;
@@ -376,14 +382,16 @@ static char **make_char_array(char **old_pos, register uint fields,
 
 /** Read 'count' number of buffer pointers into memory. */
 
-static BUFFPEK *read_buffpek_from_file(IO_CACHE *buffpek_pointers, uint count)
+static uchar *read_buffpek_from_file(IO_CACHE *buffpek_pointers, uint count,
+                                     uchar *buf)
 {
-  ulong length;
-  BUFFPEK *tmp;
+  ulong length= sizeof(BUFFPEK)*count;
+  uchar *tmp= buf;
   DBUG_ENTER("read_buffpek_from_file");
   if (count > UINT_MAX/sizeof(BUFFPEK))
     return 0; /* sizeof(BUFFPEK)*count will overflow */
-  tmp=(BUFFPEK*) my_malloc(length=sizeof(BUFFPEK)*count, MYF(MY_WME));
+  if (!tmp)
+    tmp= (uchar *)my_malloc(length, MYF(MY_WME));
   if (tmp)
   {
     if (reinit_io_cache(buffpek_pointers,READ_CACHE,0L,0,0) ||
diff --git a/sql/item.cc b/sql/item.cc
index c33e5da0ca4..463de3e1c52 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -4460,7 +4460,7 @@ Field *Item::tmp_table_field_from_field_type(TABLE *table, bool fixed_length)
     break;
   case MYSQL_TYPE_NEWDATE:
   case MYSQL_TYPE_DATE:
-    field= new Field_date(maybe_null, name, &my_charset_bin);
+    field= new Field_newdate(maybe_null, name, &my_charset_bin);
     break;
   case MYSQL_TYPE_TIME:
     field= new Field_time(maybe_null, name, &my_charset_bin);
@@ -6695,6 +6695,8 @@ enum_field_types Item_type_holder::get_real_type(Item *item)
     */
     Field *field= ((Item_field *) item)->field;
     enum_field_types type= field->real_type();
+    if (field->is_created_from_null_item)
+      return MYSQL_TYPE_NULL;
     /* work around about varchar type field detection */
     if (type == MYSQL_TYPE_STRING && field->type() == MYSQL_TYPE_VAR_STRING)
       return MYSQL_TYPE_VAR_STRING;
@@ -6948,6 +6950,8 @@ Field *Item_type_holder::make_field_by_type(TABLE *table)
     if (field)
       field->init(table);
     return field;
+  case MYSQL_TYPE_NULL:
+    return make_string_field(table);
   default:
     break;
   }
diff --git a/sql/item_sum.cc b/sql/item_sum.cc
index 19c71cbc48d..91198d0fb7e 100644
--- a/sql/item_sum.cc
+++ b/sql/item_sum.cc
@@ -632,7 +632,7 @@ Field *Item_sum_hybrid::create_tmp_field(bool group, TABLE *table,
   */
   switch (args[0]->field_type()) {
   case MYSQL_TYPE_DATE:
-    field= new Field_date(maybe_null, name, collation.collation);
+    field= new Field_newdate(maybe_null, name, collation.collation);
     break;
   case MYSQL_TYPE_TIME:
     field= new Field_time(maybe_null, name, collation.collation);
@@ -2863,44 +2863,51 @@ String *Item_sum_udf_str::val_str(String *str)
  concat of values from "group by" operation
 
  BUGS
-   DISTINCT and ORDER BY only works if ORDER BY uses all fields and only fields
-   in expression list
    Blobs doesn't work with DISTINCT or ORDER BY
 *****************************************************************************/
 
-/**
-  function of sort for syntax: GROUP_CONCAT(DISTINCT expr,...)
+
+
+/** 
+  Compares the values for fields in expr list of GROUP_CONCAT.
+  @note
+       
+     GROUP_CONCAT([DISTINCT] expr [,expr ...]
+              [ORDER BY {unsigned_integer | col_name | expr}
+                  [ASC | DESC] [,col_name ...]]
+              [SEPARATOR str_val])
+ 
+  @return
+  @retval -1 : key1 < key2 
+  @retval  0 : key1 = key2
+  @retval  1 : key1 > key2 
 */
 
-int group_concat_key_cmp_with_distinct(void* arg, uchar* key1,
-				       uchar* key2)
+int group_concat_key_cmp_with_distinct(void* arg, const void* key1, 
+                                       const void* key2)
 {
-  Item_func_group_concat* grp_item= (Item_func_group_concat*)arg;
-  TABLE *table= grp_item->table;
-  Item **field_item, **end;
+  Item_func_group_concat *item_func= (Item_func_group_concat*)arg;
+  TABLE *table= item_func->table;
 
-  for (field_item= grp_item->args, end= field_item + grp_item->arg_count_field;
-       field_item < end;
-       field_item++)
+  for (uint i= 0; i < item_func->arg_count_field; i++)
   {
+    Item *item= item_func->args[i];
+    /* 
+      If field_item is a const item then either get_tp_table_field returns 0
+      or it is an item over a const table. 
+    */
+    if (item->const_item())
+      continue;
     /*
       We have to use get_tmp_table_field() instead of
       real_item()->get_tmp_table_field() because we want the field in
       the temporary table, not the original field
     */
-    Field *field= (*field_item)->get_tmp_table_field();
-    /* 
-      If field_item is a const item then either get_tmp_table_field returns 0
-      or it is an item over a const table. 
-    */
-    if (field && !(*field_item)->const_item())
-    {
-      int res;
-      uint offset= (field->offset(field->table->record[0]) - 
-                    table->s->null_bytes);
-      if ((res= field->cmp(key1 + offset, key2 + offset)))
-	return res;
-    }
+    Field *field= item->get_tmp_table_field();
+    int res;
+    uint offset= field->offset(field->table->record[0])-table->s->null_bytes;
+    if((res= field->cmp((uchar*)key1 + offset, (uchar*)key2 + offset)))
+      return res;
   }
   return 0;
 }
@@ -2910,7 +2917,8 @@ int group_concat_key_cmp_with_distinct(void* arg, uchar* key1,
   function of sort for syntax: GROUP_CONCAT(expr,... ORDER BY col,... )
 */
 
-int group_concat_key_cmp_with_order(void* arg, uchar* key1, uchar* key2)
+int group_concat_key_cmp_with_order(void* arg, const void* key1, 
+                                    const void* key2)
 {
   Item_func_group_concat* grp_item= (Item_func_group_concat*) arg;
   ORDER **order_item, **end;
@@ -2936,7 +2944,7 @@ int group_concat_key_cmp_with_order(void* arg, uchar* key1, uchar* key2)
       int res;
       uint offset= (field->offset(field->table->record[0]) -
                     table->s->null_bytes);
-      if ((res= field->cmp(key1 + offset, key2 + offset)))
+      if ((res= field->cmp((uchar*)key1 + offset, (uchar*)key2 + offset)))
         return (*order_item)->asc ? res : -res;
     }
   }
@@ -2950,25 +2958,6 @@ int group_concat_key_cmp_with_order(void* arg, uchar* key1, uchar* key2)
 
 
 /**
-  function of sort for syntax:
-  GROUP_CONCAT(DISTINCT expr,... ORDER BY col,... ).
-
-  @bug
-    This doesn't work in the case when the order by contains data that
-    is not part of the field list because tree-insert will not notice
-    the duplicated values when inserting things sorted by ORDER BY
-*/
-
-int group_concat_key_cmp_with_distinct_and_order(void* arg,uchar* key1,
-						 uchar* key2)
-{
-  if (!group_concat_key_cmp_with_distinct(arg,key1,key2))
-    return 0;
-  return(group_concat_key_cmp_with_order(arg,key1,key2));
-}
-
-
-/**
   Append data from current leaf to item->result.
 */
 
@@ -3054,7 +3043,7 @@ Item_func_group_concat(Name_resolution_context *context_arg,
                        bool distinct_arg, List<Item> *select_list,
                        SQL_LIST *order_list, String *separator_arg)
   :tmp_table_param(0), warning(0),
-   separator(separator_arg), tree(0), table(0),
+   separator(separator_arg), tree(0), unique_filter(NULL), table(0),
    order(0), context(context_arg),
    arg_count_order(order_list ? order_list->elements : 0),
    arg_count_field(select_list->elements),
@@ -3109,6 +3098,7 @@ Item_func_group_concat::Item_func_group_concat(THD *thd,
   warning(item->warning),
   separator(item->separator),
   tree(item->tree),
+  unique_filter(item->unique_filter),
   table(item->table),
   order(item->order),
   context(item->context),
@@ -3159,6 +3149,11 @@ void Item_func_group_concat::cleanup()
         delete_tree(tree);
         tree= 0;
       }
+      if (unique_filter)
+      {
+        delete unique_filter;
+        unique_filter= NULL;
+      }
       if (warning)
       {
         char warn_buff[MYSQL_ERRMSG_SIZE];
@@ -3188,6 +3183,8 @@ void Item_func_group_concat::clear()
   no_appended= TRUE;
   if (tree)
     reset_tree(tree);
+  if (distinct)
+    unique_filter->reset();
   /* No need to reset the table as we never call write_row */
 }
 
@@ -3211,9 +3208,19 @@ bool Item_func_group_concat::add()
   }
 
   null_value= FALSE;
+  bool row_eligible= TRUE;
+
+  if (distinct) 
+  {
+    /* Filter out duplicate rows. */
+    uint count= unique_filter->elements_in_tree();
+    unique_filter->unique_add(table->record[0] + table->s->null_bytes);
+    if (count == unique_filter->elements_in_tree())
+      row_eligible= FALSE;
+  }
 
   TREE_ELEMENT *el= 0;                          // Only for safety
-  if (tree)
+  if (row_eligible && tree)
     el= tree_insert(tree, table->record[0] + table->s->null_bytes, 0,
                     tree->custom_arg);
   /*
@@ -3221,7 +3228,7 @@ bool Item_func_group_concat::add()
     we can dump the row here in case of GROUP_CONCAT(DISTINCT...)
     instead of doing tree traverse later.
   */
-  if (!warning_for_row &&
+  if (row_eligible && !warning_for_row &&
       (!tree || (el->count == 1 && distinct && !arg_count_order)))
     dump_leaf_key(table->record[0] + table->s->null_bytes, 1, this);
 
@@ -3297,7 +3304,6 @@ bool Item_func_group_concat::setup(THD *thd)
 {
   List<Item> list;
   SELECT_LEX *select_lex= thd->lex->current_select;
-  qsort_cmp2 compare_key;
   DBUG_ENTER("Item_func_group_concat::setup");
 
   /*
@@ -3387,38 +3393,33 @@ bool Item_func_group_concat::setup(THD *thd)
   table->file->extra(HA_EXTRA_NO_ROWS);
   table->no_rows= 1;
 
+  /*
+     Need sorting or uniqueness: init tree and choose a function to sort.
+     Don't reserve space for NULLs: if any of gconcat arguments is NULL,
+     the row is not added to the result.
+  */
+  uint tree_key_length= table->s->reclength - table->s->null_bytes;
 
-  if (distinct || arg_count_order)
+  if (arg_count_order)
   {
-    /*
-      Need sorting: init tree and choose a function to sort.
-      Don't reserve space for NULLs: if any of gconcat arguments is NULL,
-      the row is not added to the result.
-    */
-    uint tree_key_length= table->s->reclength - table->s->null_bytes;
-
     tree= &tree_base;
-    if (arg_count_order)
-    {
-      if (distinct)
-        compare_key= (qsort_cmp2) group_concat_key_cmp_with_distinct_and_order;
-      else
-        compare_key= (qsort_cmp2) group_concat_key_cmp_with_order;
-    }
-    else
-    {
-      compare_key= (qsort_cmp2) group_concat_key_cmp_with_distinct;
-    }
     /*
-      Create a tree for sorting. The tree is used to sort and to remove
-      duplicate values (according to the syntax of this function). If there
-      is no DISTINCT or ORDER BY clauses, we don't create this tree.
+      Create a tree for sorting. The tree is used to sort (according to the
+      syntax of this function). If there is no ORDER BY clause, we don't
+      create this tree.
     */
     init_tree(tree, (uint) min(thd->variables.max_heap_table_size,
                                thd->variables.sortbuff_size/16), 0,
-              tree_key_length, compare_key, 0, NULL, (void*) this);
+              tree_key_length, 
+              group_concat_key_cmp_with_order , 0, NULL, (void*) this);
   }
 
+  if (distinct)
+    unique_filter= new Unique(group_concat_key_cmp_with_distinct,
+                              (void*)this,
+                              tree_key_length,
+                              thd->variables.max_heap_table_size);
+  
   DBUG_RETURN(FALSE);
 }
 
@@ -3488,3 +3489,10 @@ void Item_func_group_concat::print(String *str)
   str->append(*separator);
   str->append(STRING_WITH_LEN("\')"));
 }
+
+
+Item_func_group_concat::~Item_func_group_concat()
+{
+  if (unique_filter) 
+    delete unique_filter;    
+}
diff --git a/sql/item_sum.h b/sql/item_sum.h
index b3a382012f1..a3582967736 100644
--- a/sql/item_sum.h
+++ b/sql/item_sum.h
@@ -1173,11 +1173,22 @@ class Item_func_group_concat : public Item_sum
   String *separator;
   TREE tree_base;
   TREE *tree;
+
+  /**
+     If DISTINCT is used with this GROUP_CONCAT, this member is used to filter
+     out duplicates. 
+     @see Item_func_group_concat::setup
+     @see Item_func_group_concat::add
+     @see Item_func_group_concat::clear
+   */
+  Unique *unique_filter;
   TABLE *table;
   ORDER **order;
   Name_resolution_context *context;
-  uint arg_count_order;               // total count of ORDER BY items
-  uint arg_count_field;               // count of arguments
+  /** The number of ORDER BY items. */
+  uint arg_count_order;
+  /** The number of selected items, aka the expr list. */
+  uint arg_count_field;
   uint count_cut_values;
   bool distinct;
   bool warning_for_row;
@@ -1190,13 +1201,10 @@ class Item_func_group_concat : public Item_sum
   */
   Item_func_group_concat *original;
 
-  friend int group_concat_key_cmp_with_distinct(void* arg, uchar* key1,
-					      uchar* key2);
-  friend int group_concat_key_cmp_with_order(void* arg, uchar* key1,
-					     uchar* key2);
-  friend int group_concat_key_cmp_with_distinct_and_order(void* arg,
-							uchar* key1,
-							uchar* key2);
+  friend int group_concat_key_cmp_with_distinct(void* arg, const void* key1,
+                                                const void* key2);
+  friend int group_concat_key_cmp_with_order(void* arg, const void* key1,
+					     const void* key2);
   friend int dump_leaf_key(uchar* key,
                            element_count count __attribute__((unused)),
 			   Item_func_group_concat *group_concat_item);
@@ -1207,7 +1215,7 @@ public:
                          SQL_LIST *is_order, String *is_separator);
 
   Item_func_group_concat(THD *thd, Item_func_group_concat *item);
-  ~Item_func_group_concat() {}
+  ~Item_func_group_concat();
   void cleanup();
 
   enum Sumfunctype sum_func () const {return GROUP_CONCAT_FUNC;}
diff --git a/sql/item_timefunc.cc b/sql/item_timefunc.cc
index ce760b8fd2a..a0beadcd481 100644
--- a/sql/item_timefunc.cc
+++ b/sql/item_timefunc.cc
@@ -3360,6 +3360,8 @@ bool Item_func_last_day::get_date(MYSQL_TIME *ltime, uint fuzzy_date)
   ltime->day= days_in_month[month_idx];
   if ( month_idx == 1 && calc_days_in_year(ltime->year) == 366)
     ltime->day= 29;
+  ltime->hour= ltime->minute= ltime->second= 0;
+  ltime->second_part= 0;
   ltime->time_type= MYSQL_TIMESTAMP_DATE;
   return 0;
 }
diff --git a/sql/log.cc b/sql/log.cc
index ba457b3e10b..3a09acd8fca 100644
--- a/sql/log.cc
+++ b/sql/log.cc
@@ -3018,10 +3018,10 @@ err:
 void MYSQL_BIN_LOG::make_log_name(char* buf, const char* log_ident)
 {
   uint dir_len = dirname_length(log_file_name); 
-  if (dir_len > FN_REFLEN)
+  if (dir_len >= FN_REFLEN)
     dir_len=FN_REFLEN-1;
   strnmov(buf, log_file_name, dir_len);
-  strmake(buf+dir_len, log_ident, FN_REFLEN - dir_len);
+  strmake(buf+dir_len, log_ident, FN_REFLEN - dir_len -1);
 }
 
 
diff --git a/sql/repl_failsafe.cc b/sql/repl_failsafe.cc
index d33c81b55e8..589ee8b2605 100644
--- a/sql/repl_failsafe.cc
+++ b/sql/repl_failsafe.cc
@@ -946,7 +946,7 @@ bool load_master_data(THD* thd)
 			     0, (SLAVE_IO | SLAVE_SQL)))
           my_message(ER_MASTER_INFO, ER(ER_MASTER_INFO), MYF(0));
 	strmake(active_mi->master_log_name, row[0],
-		sizeof(active_mi->master_log_name));
+		sizeof(active_mi->master_log_name) -1);
 	active_mi->master_log_pos= my_strtoll10(row[1], (char**) 0, &error_2);
         /* at least in recent versions, the condition below should be false */
 	if (active_mi->master_log_pos < BIN_LOG_HEADER_SIZE)
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index 9e4dceff87d..41596b4faf2 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -6400,7 +6400,36 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter,
         *resolution= RESOLVED_IGNORING_ALIAS;
         break;
       }
-    } 
+    }
+    else if (table_name && item->type() == Item::REF_ITEM &&
+             ((Item_ref *)item)->ref_type() == Item_ref::VIEW_REF)
+    {
+      /*
+        TODO:Here we process prefixed view references only. What we should 
+        really do is process all types of Item_refs. But this will currently 
+        lead to a clash with the way references to outer SELECTs (from the 
+        HAVING clause) are handled in e.g. :
+        SELECT 1 FROM t1 AS t1_o GROUP BY a
+          HAVING (SELECT t1_o.a FROM t1 AS t1_i GROUP BY t1_i.a LIMIT 1).
+        Processing all Item_refs here will cause t1_o.a to resolve to itself.
+        We still need to process the special case of Item_direct_view_ref 
+        because in the context of views they have the same meaning as 
+        Item_field for tables.
+      */
+      Item_ident *item_ref= (Item_ident *) item;
+      if (item_ref->name && item_ref->table_name &&
+          !my_strcasecmp(system_charset_info, item_ref->name, field_name) &&
+          !my_strcasecmp(table_alias_charset, item_ref->table_name,
+                         table_name) &&
+          (!db_name || (item_ref->db_name && 
+                        !strcmp (item_ref->db_name, db_name))))
+      {
+        found= li.ref();
+        *counter= i;
+        *resolution= RESOLVED_IGNORING_ALIAS;
+        break;
+      }
+    }
   }
   if (!found)
   {
diff --git a/sql/sql_db.cc b/sql/sql_db.cc
index f158b5488d0..b5f49b97ec9 100644
--- a/sql/sql_db.cc
+++ b/sql/sql_db.cc
@@ -1396,7 +1396,7 @@ static void backup_current_db_name(THD *thd,
   }
   else
   {
-    strmake(saved_db_name->str, thd->db, saved_db_name->length);
+    strmake(saved_db_name->str, thd->db, saved_db_name->length - 1);
     saved_db_name->length= thd->db_length;
   }
 }
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index c735f70529e..d77fa6bbb04 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -9341,6 +9341,8 @@ static Field *create_tmp_field_from_item(THD *thd, Item *item, TABLE *table,
     *((*copy_func)++) = item;			// Save for copy_funcs
   if (modify_item)
     item->set_result_field(new_field);
+  if (item->type() == Item::NULL_ITEM)
+    new_field->is_created_from_null_item= TRUE;
   return new_field;
 }
 
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 9fa4f8585f5..9cccc7c724e 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -6162,6 +6162,14 @@ select_paren:
               my_parse_error(ER(ER_SYNTAX_ERROR));
               MYSQL_YYABORT;
             }
+            if (sel->linkage == UNION_TYPE &&
+                sel->olap != UNSPECIFIED_OLAP_TYPE &&
+                sel->master_unit()->fake_select_lex)
+            {
+ 	       my_error(ER_WRONG_USAGE, MYF(0),
+                        "CUBE/ROLLUP", "ORDER BY");
+               MYSQL_YYABORT;
+            }
             /* select in braces, can't contain global parameters */
             if (sel->master_unit()->fake_select_lex)
               sel->master_unit()->global_parameters=
@@ -8050,7 +8058,8 @@ order_clause:
             SELECT_LEX *sel= lex->current_select;
             SELECT_LEX_UNIT *unit= sel-> master_unit();
             if (sel->linkage != GLOBAL_OPTIONS_TYPE &&
-                sel->olap != UNSPECIFIED_OLAP_TYPE)
+                sel->olap != UNSPECIFIED_OLAP_TYPE &&
+                (sel->linkage != UNION_TYPE || sel->braces))
             {
               my_error(ER_WRONG_USAGE, MYF(0),
                        "CUBE/ROLLUP", "ORDER BY");
diff --git a/sql/unireg.cc b/sql/unireg.cc
index dbdefd8d5b1..aab3f5606a8 100644
--- a/sql/unireg.cc
+++ b/sql/unireg.cc
@@ -227,6 +227,14 @@ bool mysql_create_frm(THD *thd, const char *file_name,
   strmake((char*) forminfo+47, create_info->comment.str ?
           create_info->comment.str : "", create_info->comment.length);
   forminfo[46]=(uchar) create_info->comment.length;
+#ifdef EXTRA_DEBUG
+  /*
+    EXTRA_DEBUG causes strmake() to initialize its buffer behind the
+    payload with a magic value to detect wrong buffer-sizes. We
+    explicitly zero that segment again.
+  */
+  memset((char*) forminfo+47 + forminfo[46], 0, 61 - forminfo[46]);
+#endif
 #ifdef WITH_PARTITION_STORAGE_ENGINE
   if (part_info)
   {