BTREE-indexes in HEAP tables can now be used to optimize ORDER BY

Don't read character set files if we are using only the default charset. In most cases the user will not anymore get a warning about missing character set files
Compare strings with space extend instead of space strip. Now the following comparisons holds:  "a" == "a " and "a\t" < "a". (Bug #3152).
Note: Because of the above fix, one has to do a REPAIR on any table that has an ascii character < 32 last in a CHAR/VARCHAR/TEXT columns.

1 files changed, 2 insertions, 0 deletions

diff --git a/sql/ha_heap.h b/sql/ha_heap.h
index c369c7029b4..feadc0c3c0f 100644
--- a/sql/ha_heap.h
+++ b/sql/ha_heap.h
@@ -26,6 +26,7 @@
 class ha_heap: public handler
 {
   HP_INFO *file;
+  key_map btree_keys;
 
  public:
   ha_heap(TABLE *table): handler(table), file(0) {}
@@ -49,6 +50,7 @@ class ha_heap: public handler
 	    (HA_ONLY_WHOLE_INDEX | HA_WRONG_ASCII_ORDER |
 	     HA_NOT_READ_PREFIX_LAST));
   }
+  const key_map *keys_to_use_for_scanning() { return &btree_keys; }
   uint max_record_length() const { return HA_MAX_REC_LENGTH; }
   uint max_keys()          const { return MAX_KEY; }
   uint max_key_parts()     const { return MAX_REF_PARTS; }