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MDEV-5992: EITS: Selectivity of non-indexed condition is counted twice in table's fanout

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MDEV-5984: EITS: Incorrect filtered% value for single-table select with range access
- Fix calculate_cond_selectivity_for_table() to work correctly with range accesses 
  over multi-component keys:
  = First, take selectivity of all possible range scans into account. Remember which 
    fields were used bt the range scans.
  = Then, calculate selectivity produced by sargable predicates on fields. If a 
    field was used in a possible range access, assume its selectivity is already
    taken into account.
- Fix table_cond_selectivity(): when quick select is used, selectivity of
  COND(table) is taken into account in matching_candidates_in_table(). In
  table_cond_selectivity() we should not apply it for the second time.
This commit is contained in:
Sergey Petrunya
2014-04-01 09:59:51 -07:00
parent 41a2ca5c16
commit 26a3d567c9
4 changed files with 173 additions and 60 deletions
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21
mysql-test/r/selectivity_no_engine.result
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@ -118,6 +118,27 @@ Warnings:
Note 1003 select `test`.`t1`.`col1` AS `col1` from `test`.`t1` where (`test`.`t1`.`col1` <= <cache>(-(1)))
drop table t1, t2;
#
# MDEV-5984: EITS: Incorrect filtered% value for single-table select with range access
#
create table t1(a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t2 (a int, b int, col1 varchar(64), col2 varchar(64), key(a,b));
insert into t2 select A.a+10*B.a, C.a+10*D.a, 'filler-data1', 'filler-data2' from t1 A, t1 B, t1 C, t1 D;
set histogram_size=100;
set optimizer_use_condition_selectivity=4;
set use_stat_tables='preferably';
analyze table t2 persistent for all;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status Table is already up to date
# This must show filtered=100%:
explain extended select * from t2 where a in (1,2,3) and b in (1,2,3);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t2 range a a 10 NULL 9 100.00 Using index condition
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`col1` AS `col1`,`test`.`t2`.`col2` AS `col2` from `test`.`t2` where ((`test`.`t2`.`a` in (1,2,3)) and (`test`.`t2`.`b` in (1,2,3)))
drop table t2, t1;
#
# End of the test file
#
set use_stat_tables= @save_use_stat_tables;