Updated optimizer costs in multi_range_read_info_const() and sql_select.cc

- multi_range_read_info_const now uses the new records_in_range interface
- Added handler::avg_io_cost()
- Don't calculate avg_io_cost() in get_sweep_read_cost if avg_io_cost is
  not 1.0.  In this case we trust the avg_io_cost() from the handler.
- Changed test_quick_select to use TIME_FOR_COMPARE instead of
  TIME_FOR_COMPARE_IDX to align this with the rest of the code.
- Fixed bug when using test_if_cheaper_ordering where we didn't use
  keyread if index was changed
- Fixed a bug where we didn't use index only read when using order-by-index
- Added keyread_time() to HEAP.
  The default keyread_time() was optimized for blocks and not suitable for
  HEAP. The effect was the HEAP prefered table scans over ranges for btree
  indexes.
- Fixed get_sweep_read_cost() for HEAP tables
- Ensure that range and ref have same cost for simple ranges
  Added a small cost (MULTI_RANGE_READ_SETUP_COST) to ranges to ensure
  we favior ref for range for simple queries.
- Fixed that matching_candidates_in_table() uses same number of records
  as the rest of the optimizer
- Added avg_io_cost() to JT_EQ_REF cost. This helps calculate the cost for
  HEAP and temporary tables better. A few tests changed because of this.
- heap::read_time() and heap::keyread_time() adjusted to not add +1.
  This was to ensure that handler::keyread_time() doesn't give
  higher cost for heap tables than for normal tables. One effect of
  this is that heap and derived tables stored in heap will prefer
  key access as this is now regarded as cheap.
- Changed cost for index read in sql_select.cc to match
  multi_range_read_info_const(). All index cost calculation is now
  done trough one function.
- 'ref' will now use quick_cost for keys if it exists. This is done
  so that for '=' ranges, 'ref' is prefered over 'range'.
- scan_time() now takes avg_io_costs() into account
- get_delayed_table_estimates() uses block_size and avg_io_cost()
- Removed default argument to test_if_order_by_key(); simplifies code

1 files changed, 3 insertions, 3 deletions

diff --git a/mysql-test/main/key_cache.result b/mysql-test/main/key_cache.result
index b94d05a962f..c8bdc979387 100644
--- a/mysql-test/main/key_cache.result
+++ b/mysql-test/main/key_cache.result
@@ -739,13 +739,13 @@ p
 1019
 explain select i from t2 where a='yyyy' and i=3;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	ref	k1,k2	k1	5	const	189	Using where
+1	SIMPLE	t2	index_merge	k1,k2	k1,k2	5,11	NULL	50	Using intersect(k1,k2); Using where; Using index
 select i from t2 where a='yyyy' and i=3;
 i
 3
 explain select a from t2 where a='yyyy' and i=3;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	ref	k1,k2	k1	5	const	189	Using where
+1	SIMPLE	t2	index_merge	k1,k2	k1,k2	5,11	NULL	50	Using intersect(k1,k2); Using where; Using index
 select a from t2 where a='yyyy' and i=3 ;
 a
 yyyy
@@ -753,7 +753,7 @@ select * from information_schema.key_caches where segment_number is null;
 KEY_CACHE_NAME	SEGMENTS	SEGMENT_NUMBER	FULL_SIZE	BLOCK_SIZE	USED_BLOCKS	UNUSED_BLOCKS	DIRTY_BLOCKS	READ_REQUESTS	READS	WRITE_REQUESTS	WRITES
 default	2	NULL	32768	1024	#	#	0	3172	24	1552	18
 small	NULL	NULL	1048576	1024	#	#	0	0	0	0	0
-keycache1	7	NULL	262143	2048	#	#	0	3201	43	1594	30
+keycache1	7	NULL	262143	2048	#	#	0	3229	43	1594	30
 keycache2	NULL	NULL	1048576	1024	#	#	0	6	6	3	3
 set global keycache1.key_cache_block_size=2*1024;
 insert into t2 values (7000, 3, 'yyyy');