btr0cur.c, ha_innobase.cc:

  Fine-tune optimization parameters; in small tables the estimates are accurate; in big tables let us not be too optimistic about index selectivity


sql/ha_innobase.cc:
  Fine-tune optimization parameters; in small tables the estimates are accurate; in big tables let us not be too optimistic about index selectivity
innobase/btr/btr0cur.c:
  Fine-tune optimization parameters; in small tables the estimates are accurate; in big tables let us not be too optimistic about index selectivity

1 files changed, 0 insertions, 16 deletions

diff --git a/sql/ha_innobase.cc b/sql/ha_innobase.cc
index acdc9736a4f..a923a259ebd 100644
--- a/sql/ha_innobase.cc
+++ b/sql/ha_innobase.cc
@@ -3130,22 +3130,6 @@ ha_innobase::info(
 					rec_per_key = 1;
 				}
 			
-				/* Since the MySQL optimizer is often too
-				pessimistic in the assumption that a table
-				does not fit in the buffer pool, we
-				increase the attractiveness of indexes
-				by assuming the selectivity of any prefix
-				of an index is 1 / 100 or better.
-				(Actually, we should look at the table
-				size, and if the table is smaller than
-				the buffer pool, we should uniformly
-				increase the attractiveness of indexes,
-				regardless of the estimated selectivity.) */
-
-			        if (rec_per_key > records / 100) {
-				        rec_per_key = records / 100;
-				}
-
 				table->key_info[i].rec_per_key[j]
 								= rec_per_key;
 			}