set @innodb_stats_persistent_save= @@innodb_stats_persistent; set @innodb_stats_persistent_sample_pages_save=
@@innodb_stats_persistent_sample_pages; set global innodb_stats_persistent= 1; set global innodb_stats_persistent_sample_pages=100; SET SESSION DEFAULT_STORAGE_ENGINE='InnoDB';
select @@global.use_stat_tables;
@@global.use_stat_tables
PREFERABLY
select @@session.use_stat_tables;
@@session.use_stat_tables
PREFERABLY set @save_use_stat_tables=@@use_stat_tables; set use_stat_tables='preferably';
DROP DATABASE IF EXISTS dbt3_s001;
CREATE DATABASE dbt3_s001;
use dbt3_s001; set @save_optimizer_switch=@@optimizer_switch; set optimizer_switch='extended_keys=off'; set optimizer_switch='rowid_filter=off';
#
# Bug mdev-503: optimizer ignores setting use_stat_tables='preferably'
#
flush tables
customer, lineitem, nation, orders, part, partsupp, region, supplier; set use_stat_tables='never';
EXPLAIN select sql_calc_found_rows straight_join
l_orderkey, sum(l_extendedprice*(1-l_discount)) as revenue,
o_orderdate, o_shippriority
from orders, customer, lineitem
where c_mktsegment = 'BUILDING'and c_custkey = o_custkey and l_orderkey = o_orderkey and o_orderdate < date '1995-03-15' and l_shipdate > date '1995-03-15'
group by l_orderkey, o_orderdate, o_shippriority
order by revenue desc, o_orderdate
limit 10;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE orders ALL PRIMARY,i_o_orderdate,i_o_custkey NULL NULL NULL # Using where; Using temporary; Using filesort 1 SIMPLE customer eq_ref PRIMARY PRIMARY 4 dbt3_s001.orders.o_custkey # Using where 1 SIMPLE lineitem ref PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey # Using where set use_stat_tables='preferably';
EXPLAIN select sql_calc_found_rows straight_join
l_orderkey, sum(l_extendedprice*(1-l_discount)) as revenue,
o_orderdate, o_shippriority
from orders, customer, lineitem
where c_mktsegment = 'BUILDING'and c_custkey = o_custkey and l_orderkey = o_orderkey and o_orderdate < date '1995-03-15' and l_shipdate > date '1995-03-15'
group by l_orderkey, o_orderdate, o_shippriority
order by revenue desc, o_orderdate
limit 10;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE orders ALL PRIMARY,i_o_orderdate,i_o_custkey NULL NULL NULL 1500 Using where; Using temporary; Using filesort 1 SIMPLE customer eq_ref PRIMARY PRIMARY 4 dbt3_s001.orders.o_custkey 1 Using where 1 SIMPLE lineitem ref PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey 4 Using where
flush tables customer, orders, lineitem;
EXPLAIN select sql_calc_found_rows straight_join
l_orderkey, sum(l_extendedprice*(1-l_discount)) as revenue,
o_orderdate, o_shippriority
from orders, customer, lineitem
where c_mktsegment = 'BUILDING'and c_custkey = o_custkey and l_orderkey = o_orderkey and o_orderdate < date '1995-03-15' and l_shipdate > date '1995-03-15'
group by l_orderkey, o_orderdate, o_shippriority
order by revenue desc, o_orderdate
limit 10;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE orders ALL PRIMARY,i_o_orderdate,i_o_custkey NULL NULL NULL 1500 Using where; Using temporary; Using filesort 1 SIMPLE customer eq_ref PRIMARY PRIMARY 4 dbt3_s001.orders.o_custkey 1 Using where 1 SIMPLE lineitem ref PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey 4 Using where
# End of the test case for mdev-503 set optimizer_switch=@save_optimizer_switch;
DROP DATABASE dbt3_s001;
use test; set use_stat_tables=@save_use_stat_tables; SET SESSION DEFAULT_STORAGE_ENGINE=DEFAULT; set global innodb_stats_persistent= @innodb_stats_persistent_save; set global innodb_stats_persistent_sample_pages=
@innodb_stats_persistent_sample_pages_save;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.12 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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