postreview fixes

sql/mysql_priv.h:
  constant definition
sql/sql_base.cc:
  difine used instead of constant
sql/sql_cache.cc:
  difine used instead of constant
  typo fixed

sql/mysql_priv.h

@@ -551,6 +551,7 @@ int mysql_ha_flush(THD *thd, TABLE_LIST *tables, uint mode_flags);
 #define MYSQL_HA_FLUSH_ALL          0x02
 
 /* sql_base.cc */
+#define TMP_TABLE_KEY_EXTRA 8
 void set_item_name(Item *item,char *pos,uint length);
 bool add_field_to_list(char *field_name, enum enum_field_types type,
 		       char *length, char *decimal,

sql/sql_base.cc

@@ -816,8 +816,9 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
 
   for (table=thd->temporary_tables; table ; table=table->next)
   {
-    if (table->key_length == key_length+8 &&
-	!memcmp(table->table_cache_key,key,key_length+8))
+    if (table->key_length == key_length + TMP_TABLE_KEY_EXTRA &&
+	!memcmp(table->table_cache_key, key,
+                key_length + TMP_TABLE_KEY_EXTRA))
     {
       if (table->query_id == thd->query_id)
       {

sql/sql_cache.cc

@@ -983,7 +983,7 @@ Query_cache::send_result_to_client(THD *thd, char *sql, uint query_length)
     */
     for (tmptable= thd->temporary_tables; tmptable ; tmptable= tmptable->next)
     {
-      if (tmptable->key_length - 8 == table->key_len() &&
+      if (tmptable->key_length - TMP_TABLE_KEY_EXTRA == table->key_len() &&
           !memcmp(tmptable->table_cache_key, table->data(),
                   table->key_len()))
       {
@@ -993,7 +993,7 @@ Query_cache::send_result_to_client(THD *thd, char *sql, uint query_length)
         STRUCT_UNLOCK(&structure_guard_mutex);
         /*
           We should not store result of this query because it contain
-          temporary tables => assign following wariable to make check
+          temporary tables => assign following variable to make check
           faster.
         */
         thd->safe_to_cache_query=0;