Fixed LP bug #799499.

The following were missing in the patch for mwl106:
- KEY_PART_INFO::fieldnr were not set for generated keys to access
  tmp tables storing the rows of materialized derived tables/views
- TABLE_SHARE::column_bitmap_size was not set for tmp tables storing
  the rows of materialized derived tables/views.
These could cause crashes or memory overwrite.

mysql-test/r/derived.result

@@ -441,3 +441,26 @@ SELECT MAX(b) FROM (SELECT * FROM t1) AS t WHERE a = 100;
 MAX(b)
 5
 DROP TABLE t1;
+#
+#  LP bug #799499: query over a materialized view 
+#                  accessed by a key
+#
+CREATE TABLE t1 (a int) ;
+INSERT INTO t1 VALUES (8);
+CREATE TABLE t2 (a int, b int) ;
+INSERT INTO t2 VALUES
+(262, NULL), (253, 190), (260, NULL), (250, 163), (188, 8),
+(257,200), (256, NULL), (255, 8), (249, NULL), (259, 7);
+CREATE VIEW v1 AS SELECT a, MIN(b) AS b FROM t2 GROUP BY a;
+EXPLAIN
+SELECT * FROM v1, t1 WHERE v1.b=t1.a  ORDER BY v1.a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	Using filesort
+1	PRIMARY	<derived2>	ref	key0	key0	5	const	1	Using where
+2	DERIVED	t2	ALL	NULL	NULL	NULL	NULL	10	Using temporary; Using filesort
+SELECT * FROM v1, t1 WHERE v1.b=t1.a  ORDER BY v1.a;
+a	b	a
+188	8	8
+255	8	8
+DROP VIEW v1;
+DROP TABLE t1,t2;

mysql-test/t/derived.test

@@ -348,3 +348,24 @@ SELECT MAX(b) FROM (SELECT * FROM t1) AS t WHERE a = 100;
 
 DROP TABLE t1;
 
+--echo #
+--echo #  LP bug #799499: query over a materialized view 
+--echo #                  accessed by a key
+--echo #
+
+CREATE TABLE t1 (a int) ;
+INSERT INTO t1 VALUES (8);
+
+CREATE TABLE t2 (a int, b int) ;
+INSERT INTO t2 VALUES
+  (262, NULL), (253, 190), (260, NULL), (250, 163), (188, 8),
+  (257,200), (256, NULL), (255, 8), (249, NULL), (259, 7);
+
+CREATE VIEW v1 AS SELECT a, MIN(b) AS b FROM t2 GROUP BY a;
+
+EXPLAIN
+SELECT * FROM v1, t1 WHERE v1.b=t1.a  ORDER BY v1.a;
+SELECT * FROM v1, t1 WHERE v1.b=t1.a  ORDER BY v1.a;
+
+DROP VIEW v1;
+DROP TABLE t1,t2;

sql/sql_select.cc

@@ -7151,7 +7151,8 @@ static bool create_hj_key_for_table(JOIN *join, JOIN_TAB *join_tab,
         (first_keyuse || keyuse->keypart != (keyuse-1)->keypart))
     {
       Field *field= table->field[keyuse->keypart];
-      table->create_key_part_by_field(keyinfo, key_part_info, field);
+      uint fieldnr= keyuse->keypart+1;
+      table->create_key_part_by_field(keyinfo, key_part_info, field, fieldnr);
       first_keyuse= FALSE;
       key_part_info++;
     }
@@ -13312,6 +13313,7 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
   *reg_field= 0;
   *blob_field= 0;				// End marker
   share->fields= field_count;
+  share->column_bitmap_size= bitmap_buffer_size(share->fields);
 
   /* If result table is small; use a heap */
   /* future: storage engine selection can be made dynamic? */

sql/table.cc

@@ -5241,13 +5241,14 @@ bool TABLE::alloc_keys(uint key_count)
 
 void TABLE::create_key_part_by_field(KEY *keyinfo,
                                      KEY_PART_INFO *key_part_info,
-                                     Field *field)
+                                     Field *field, uint fieldnr)
 {   
   field->flags|= PART_KEY_FLAG;
   key_part_info->null_bit= field->null_bit;
   key_part_info->null_offset= (uint) (field->null_ptr -
                                       (uchar*) record[0]);
   key_part_info->field= field;
+  key_part_info->fieldnr= fieldnr;
   key_part_info->offset= field->offset(record[0]);
   key_part_info->length=   (uint16) field->pack_length();
   keyinfo->key_length+= key_part_info->length;
@@ -5340,11 +5341,12 @@ bool TABLE::add_tmp_key(uint key, uint key_parts,
 
   for (i= 0; i < key_parts; i++)
   {
-    reg_field= field + next_field_no(arg);
+    uint fld_idx= next_field_no(arg); 
+    reg_field= field + fld_idx;
     if (key_start)
       (*reg_field)->key_start.set_bit(key);
     (*reg_field)->part_of_key.set_bit(key);
-    create_key_part_by_field(keyinfo, key_part_info, *reg_field);
+    create_key_part_by_field(keyinfo, key_part_info, *reg_field, fld_idx+1);
     key_start= FALSE;
     key_part_info++;
   }

sql/table.h

@@ -959,7 +959,7 @@ struct st_table {
                    uint (*next_field_no) (uchar *), uchar *arg,
                    bool unique);
   void create_key_part_by_field(KEY *keyinfo, KEY_PART_INFO *key_part_info,
-                                Field *field);
+                                Field *field, uint fieldnr);
   void use_index(int key_to_save);
   void set_table_map(table_map map_arg, uint tablenr_arg)
   {