This is first cset for WL#1394 "Optimize index merge when all involved index ranges include only values with equal keys"

The main idea is to exploit the fact that key scans for "key=const" return ordered sequences of rowids.


include/my_base.h:
  Added HA_EXTRA_KEYREAD_PRESERVE_FIELDS flag
include/my_bitmap.h:
  Added a couple of utility functions
include/my_sys.h:
  Added my_conunt_bits_ushort function
innobase/include/row0mysql.h:
  Added support for HA_EXTRA_KEYREAD_PRESERVE_FIELDS
innobase/row/row0sel.c:
  Added support for HA_EXTRA_KEYREAD_PRESERVE_FIELDS
mysys/my_bit.c:
  Added my_count_bits_ushort function
mysys/my_bitmap.c:
  Added a couple of utility functions
sql/ha_berkeley.cc:
  Added cmp_ref rowid comparison function.
sql/ha_berkeley.h:
  Added cmp_ref rowid comparison function.
sql/ha_heap.h:
  Added cmp_ref rowid comparison function.
sql/ha_innodb.cc:
  Added cmp_ref rowid comparison function and support from HA_EXTRA_KEYREAD_PRESERVE_FIELDS
sql/ha_innodb.h:
  Added cmp_ref rowid comparison function.
sql/handler.h:
  Added cmp_ref rowid comparison function.
sql/opt_range.cc:
  Added QUICK_ROR_{INTERSECT,UNION}_SELECT classes and related optimizer code
sql/opt_range.h:
  Added QUICK_ROR_{INTERSECT,UNION}_SELECT classes
sql/sql_delete.cc:
  Changed to use new ROWID comparison function
  also always call quick->reset() for quick selects
sql/sql_select.cc:
  Account for new quick select types
sql/sql_select.h:
  New, proper rowid ordering/comparison function to be used with Unique class etc.
sql/sql_test.cc:
  Account for new quick select types
sql/sql_update.cc:
  Account for new quick select types

3 files changed, 10 insertions, 1 deletions

diff --git a/include/my_base.h b/include/my_base.h
index 89b46de520f..19843d413c4 100644
--- a/include/my_base.h
+++ b/include/my_base.h
@@ -132,7 +132,13 @@ enum ha_extra_function {
   HA_EXTRA_RETRIEVE_ALL_COLS,
   HA_EXTRA_PREPARE_FOR_DELETE,
   HA_EXTRA_PREPARE_FOR_UPDATE,		/* Remove read cache if problems */
-  HA_EXTRA_PRELOAD_BUFFER_SIZE          /* Set buffer size for preloading */
+  HA_EXTRA_PRELOAD_BUFFER_SIZE,          /* Set buffer size for preloading */
+  /*
+    When using HA_EXTRA_KEYREAD, overwrite only key member fields and keep 
+    other fields intact. When this is off (by default) InnoDB will use memcpy
+    to overwrite entire row.
+  */
+  HA_EXTRA_KEYREAD_PRESERVE_FIELDS
 };
 
 	/* The following is parameter to ha_panic() */
diff --git a/include/my_bitmap.h b/include/my_bitmap.h
index 5b3da011f54..bb59cead092 100644
--- a/include/my_bitmap.h
+++ b/include/my_bitmap.h
@@ -46,6 +46,8 @@ extern my_bool bitmap_is_set(const MY_BITMAP *map, uint bitmap_bit);
 extern my_bool bitmap_is_set_all(const MY_BITMAP *map);
 extern my_bool bitmap_is_subset(const MY_BITMAP *map1, const MY_BITMAP *map2);
 extern uint bitmap_set_next(MY_BITMAP *map);
+extern uint bitmap_get_first(const MY_BITMAP *map);
+extern uint bitmap_bits_set(const MY_BITMAP *map);
 extern void bitmap_clear_all(MY_BITMAP *map);
 extern void bitmap_clear_bit(MY_BITMAP *map, uint bitmap_bit);
 extern void bitmap_free(MY_BITMAP *map);
diff --git a/include/my_sys.h b/include/my_sys.h
index d24bef11182..5e7108f552a 100644
--- a/include/my_sys.h
+++ b/include/my_sys.h
@@ -744,6 +744,7 @@ extern byte *my_compress_alloc(const byte *packet, ulong *len, ulong *complen);
 extern ha_checksum my_checksum(ha_checksum crc, const byte *mem, uint count);
 extern uint my_bit_log2(ulong value);
 extern uint my_count_bits(ulonglong v);
+extern uint my_count_bits_ushort(ushort v);
 extern void my_sleep(ulong m_seconds);
 extern ulong crc32(ulong crc, const uchar *buf, uint len);