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|
select @@global.use_stat_tables;
@@global.use_stat_tables
COMPLEMENTARY
select @@session.use_stat_tables;
@@session.use_stat_tables
COMPLEMENTARY
set @save_use_stat_tables=@@use_stat_tables;
set @save_histogram_size=@@global.histogram_size;
set @@global.histogram_size=0,@@local.histogram_size=0;
set optimizer_use_condition_selectivity=1;
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';
select * from mysql.table_stats;
db_name table_name cardinality
dbt3_s001 customer 150
dbt3_s001 lineitem 6005
dbt3_s001 nation 25
dbt3_s001 orders 1500
dbt3_s001 part 200
dbt3_s001 partsupp 700
dbt3_s001 region 5
dbt3_s001 supplier 10
select * from mysql.index_stats;
db_name table_name index_name prefix_arity avg_frequency
dbt3_s001 customer PRIMARY 1 1.0000
dbt3_s001 customer i_c_nationkey 1 6.0000
dbt3_s001 lineitem PRIMARY 1 4.0033
dbt3_s001 lineitem PRIMARY 2 1.0000
dbt3_s001 lineitem i_l_shipdate 1 2.6500
dbt3_s001 lineitem i_l_suppkey_partkey 1 30.0250
dbt3_s001 lineitem i_l_suppkey_partkey 2 8.5786
dbt3_s001 lineitem i_l_partkey 1 30.0250
dbt3_s001 lineitem i_l_suppkey 1 600.5000
dbt3_s001 lineitem i_l_receiptdate 1 2.6477
dbt3_s001 lineitem i_l_orderkey 1 4.0033
dbt3_s001 lineitem i_l_orderkey_quantity 1 4.0033
dbt3_s001 lineitem i_l_orderkey_quantity 2 1.0404
dbt3_s001 lineitem i_l_commitdate 1 2.7160
dbt3_s001 nation PRIMARY 1 1.0000
dbt3_s001 nation i_n_regionkey 1 5.0000
dbt3_s001 orders PRIMARY 1 1.0000
dbt3_s001 orders i_o_orderdate 1 1.3321
dbt3_s001 orders i_o_custkey 1 15.0000
dbt3_s001 part PRIMARY 1 1.0000
dbt3_s001 part i_p_retailprice 1 1.0000
dbt3_s001 partsupp PRIMARY 1 3.5000
dbt3_s001 partsupp PRIMARY 2 1.0000
dbt3_s001 partsupp i_ps_partkey 1 3.5000
dbt3_s001 partsupp i_ps_suppkey 1 70.0000
dbt3_s001 region PRIMARY 1 1.0000
dbt3_s001 supplier PRIMARY 1 1.0000
dbt3_s001 supplier i_s_nationkey 1 1.1111
set optimizer_switch=@save_optimizer_switch;
set @save_optimizer_switch=@@optimizer_switch;
set optimizer_switch='index_condition_pushdown=off';
EXPLAIN select n_name, sum(l_extendedprice * (1 - l_discount)) as revenue
from customer, orders, lineitem, supplier, nation, region
where c_custkey = o_custkey and l_orderkey = o_orderkey
and l_suppkey = s_suppkey and c_nationkey = s_nationkey
and s_nationkey = n_nationkey and n_regionkey = r_regionkey
and r_name = 'AMERICA' and o_orderdate >= date '1995-01-01'
and o_orderdate < date '1995-01-01' + interval '1' year
group by n_name
order by revenue desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE orders range PRIMARY,i_o_orderdate,i_o_custkey i_o_orderdate 4 NULL 179 Using where; Using temporary; Using filesort
1 SIMPLE customer eq_ref PRIMARY,i_c_nationkey PRIMARY 4 dbt3_s001.orders.o_custkey 1 Using where
1 SIMPLE nation eq_ref PRIMARY,i_n_regionkey PRIMARY 4 dbt3_s001.customer.c_nationkey 1
1 SIMPLE region ALL PRIMARY NULL NULL NULL 5 Using where; Using join buffer (flat, BNL join)
1 SIMPLE lineitem ref PRIMARY,i_l_suppkey,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey 4 Using where
1 SIMPLE supplier eq_ref PRIMARY,i_s_nationkey PRIMARY 4 dbt3_s001.lineitem.l_suppkey 1 Using where
select n_name, sum(l_extendedprice * (1 - l_discount)) as revenue
from customer, orders, lineitem, supplier, nation, region
where c_custkey = o_custkey and l_orderkey = o_orderkey
and l_suppkey = s_suppkey and c_nationkey = s_nationkey
and s_nationkey = n_nationkey and n_regionkey = r_regionkey
and r_name = 'AMERICA' and o_orderdate >= date '1995-01-01'
and o_orderdate < date '1995-01-01' + interval '1' year
group by n_name
order by revenue desc;
n_name revenue
PERU 321915.8715
ARGENTINA 69817.1451
set optimizer_switch=@save_optimizer_switch;
delete from mysql.index_stats;
select * from mysql.table_stats;
db_name table_name cardinality
dbt3_s001 customer 150
dbt3_s001 lineitem 6005
dbt3_s001 nation 25
dbt3_s001 orders 1500
dbt3_s001 part 200
dbt3_s001 partsupp 700
dbt3_s001 region 5
dbt3_s001 supplier 10
select * from mysql.index_stats;
db_name table_name index_name prefix_arity avg_frequency
dbt3_s001 customer PRIMARY 1 1.0000
dbt3_s001 customer i_c_nationkey 1 6.0000
dbt3_s001 lineitem PRIMARY 1 4.0033
dbt3_s001 lineitem PRIMARY 2 1.0000
dbt3_s001 lineitem i_l_shipdate 1 2.6500
dbt3_s001 lineitem i_l_suppkey_partkey 1 30.0250
dbt3_s001 lineitem i_l_suppkey_partkey 2 8.5786
dbt3_s001 lineitem i_l_partkey 1 30.0250
dbt3_s001 lineitem i_l_suppkey 1 600.5000
dbt3_s001 lineitem i_l_receiptdate 1 2.6477
dbt3_s001 lineitem i_l_orderkey 1 4.0033
dbt3_s001 lineitem i_l_orderkey_quantity 1 4.0033
dbt3_s001 lineitem i_l_orderkey_quantity 2 1.0404
dbt3_s001 lineitem i_l_commitdate 1 2.7160
dbt3_s001 nation PRIMARY 1 1.0000
dbt3_s001 nation i_n_regionkey 1 5.0000
dbt3_s001 orders PRIMARY 1 1.0000
dbt3_s001 orders i_o_orderdate 1 1.3321
dbt3_s001 orders i_o_custkey 1 15.0000
dbt3_s001 part PRIMARY 1 1.0000
dbt3_s001 part i_p_retailprice 1 1.0000
dbt3_s001 partsupp PRIMARY 1 3.5000
dbt3_s001 partsupp PRIMARY 2 1.0000
dbt3_s001 partsupp i_ps_partkey 1 3.5000
dbt3_s001 partsupp i_ps_suppkey 1 70.0000
dbt3_s001 region PRIMARY 1 1.0000
dbt3_s001 supplier PRIMARY 1 1.0000
dbt3_s001 supplier i_s_nationkey 1 1.1111
select * from mysql.table_stats where table_name='orders';
db_name table_name cardinality
dbt3_s001 orders 1500
select * from mysql.index_stats where table_name='orders';
db_name table_name index_name prefix_arity avg_frequency
dbt3_s001 orders PRIMARY 1 1.0000
dbt3_s001 orders i_o_orderdate 1 1.3321
dbt3_s001 orders i_o_custkey 1 15.0000
select (select cardinality from mysql.table_stats where table_name='orders') /
(select avg_frequency from mysql.index_stats
where index_name='i_o_orderdate' and prefix_arity=1) as n_distinct;
n_distinct
1126.0416
select count(distinct o_orderdate) from orders;
count(distinct o_orderdate)
1126
select (select cardinality from mysql.table_stats where table_name='orders') /
(select avg_frequency from mysql.index_stats
where index_name='i_o_custkey' and prefix_arity=1) as n_distinct;
n_distinct
100.0000
select count(distinct o_custkey) from orders;
count(distinct o_custkey)
100
show index from orders;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
orders 0 PRIMARY 1 o_orderkey A 1500 NULL NULL BTREE
orders 1 i_o_orderdate 1 o_orderDATE A 1126 NULL NULL YES BTREE
orders 1 i_o_custkey 1 o_custkey A 100 NULL NULL YES BTREE
select index_name, column_name, cardinality from information_schema.statistics
where table_name='orders';
index_name column_name cardinality
PRIMARY o_orderkey 1500
i_o_orderdate o_orderDATE 1126
i_o_custkey o_custkey 100
set @save_optimizer_switch=@@optimizer_switch;
set optimizer_switch='index_condition_pushdown=off';
EXPLAIN select n_name, sum(l_extendedprice * (1 - l_discount)) as revenue
from customer, orders, lineitem, supplier, nation, region
where c_custkey = o_custkey and l_orderkey = o_orderkey
and l_suppkey = s_suppkey and c_nationkey = s_nationkey
and s_nationkey = n_nationkey and n_regionkey = r_regionkey
and r_name = 'AMERICA' and o_orderdate >= date '1995-01-01'
and o_orderdate < date '1995-01-01' + interval '1' year
group by n_name
order by revenue desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE orders range PRIMARY,i_o_orderdate,i_o_custkey i_o_orderdate 4 NULL 179 Using where; Using temporary; Using filesort
1 SIMPLE customer eq_ref PRIMARY,i_c_nationkey PRIMARY 4 dbt3_s001.orders.o_custkey 1 Using where
1 SIMPLE nation eq_ref PRIMARY,i_n_regionkey PRIMARY 4 dbt3_s001.customer.c_nationkey 1
1 SIMPLE region ALL PRIMARY NULL NULL NULL 5 Using where; Using join buffer (flat, BNL join)
1 SIMPLE lineitem ref PRIMARY,i_l_suppkey,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey 4 Using where
1 SIMPLE supplier eq_ref PRIMARY,i_s_nationkey PRIMARY 4 dbt3_s001.lineitem.l_suppkey 1 Using where
select n_name, sum(l_extendedprice * (1 - l_discount)) as revenue
from customer, orders, lineitem, supplier, nation, region
where c_custkey = o_custkey and l_orderkey = o_orderkey
and l_suppkey = s_suppkey and c_nationkey = s_nationkey
and s_nationkey = n_nationkey and n_regionkey = r_regionkey
and r_name = 'AMERICA' and o_orderdate >= date '1995-01-01'
and o_orderdate < date '1995-01-01' + interval '1' year
group by n_name
order by revenue desc;
n_name revenue
PERU 321915.8715
ARGENTINA 69817.1451
set optimizer_switch=@save_optimizer_switch;
EXPLAIN select o_year,
sum(case when nation = 'UNITED STATES' then volume else 0 end) /
sum(volume) as mkt_share
from (select extract(year from o_orderdate) as o_year,
l_extendedprice * (1-l_discount) as volume,
n2.n_name as nation
from part, supplier, lineitem, orders, customer,
nation n1, nation n2, region
where p_partkey = l_partkey and s_suppkey = l_suppkey
and l_orderkey = o_orderkey and o_custkey = c_custkey
and c_nationkey = n1.n_nationkey and n1.n_regionkey = r_regionkey
and r_name = 'AMERICA' and s_nationkey = n2.n_nationkey
and o_orderdate between date '1995-01-01' and date '1996-12-31'
and p_type = 'STANDARD BRUSHED STEEL' ) as all_nations
group by o_year
order by o_year;
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,i_c_nationkey PRIMARY 4 dbt3_s001.orders.o_custkey 1 Using where
1 SIMPLE n1 eq_ref PRIMARY,i_n_regionkey PRIMARY 4 dbt3_s001.customer.c_nationkey 1
1 SIMPLE region ALL PRIMARY NULL NULL NULL 5 Using where; Using join buffer (flat, BNL join)
1 SIMPLE lineitem ref PRIMARY,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey 4 Using where
1 SIMPLE part eq_ref PRIMARY PRIMARY 4 dbt3_s001.lineitem.l_partkey 1 Using where
1 SIMPLE supplier eq_ref PRIMARY,i_s_nationkey PRIMARY 4 dbt3_s001.lineitem.l_suppkey 1 Using where
1 SIMPLE n2 eq_ref PRIMARY PRIMARY 4 dbt3_s001.supplier.s_nationkey 1
select o_year,
sum(case when nation = 'UNITED STATES' then volume else 0 end) /
sum(volume) as mkt_share
from (select extract(year from o_orderdate) as o_year,
l_extendedprice * (1-l_discount) as volume,
n2.n_name as nation
from part, supplier, lineitem, orders, customer,
nation n1, nation n2, region
where p_partkey = l_partkey and s_suppkey = l_suppkey
and l_orderkey = o_orderkey and o_custkey = c_custkey
and c_nationkey = n1.n_nationkey and n1.n_regionkey = r_regionkey
and r_name = 'AMERICA' and s_nationkey = n2.n_nationkey
and o_orderdate between date '1995-01-01' and date '1996-12-31'
and p_type = 'STANDARD BRUSHED STEEL' ) as all_nations
group by o_year
order by o_year;
o_year mkt_share
1995 0.4495521838895718
1996 0.024585468215352495
EXPLAIN select nation, o_year, sum(amount) as sum_profit
from (select n_name as nation,
extract(year from o_orderdate) as o_year,
l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount
from part, supplier, lineitem, partsupp, orders, nation
where s_suppkey = l_suppkey and ps_suppkey = l_suppkey
and ps_partkey = l_partkey and p_partkey = l_partkey
and o_orderkey = l_orderkey and s_nationkey = n_nationkey
and p_name like '%green%') as profit
group by nation, o_year
order by nation, o_year desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE supplier ALL PRIMARY,i_s_nationkey NULL NULL NULL 10 Using where; Using temporary; Using filesort
1 SIMPLE nation eq_ref PRIMARY PRIMARY 4 dbt3_s001.supplier.s_nationkey 1
1 SIMPLE partsupp ref PRIMARY,i_ps_partkey,i_ps_suppkey i_ps_suppkey 4 dbt3_s001.supplier.s_suppkey 70
1 SIMPLE part eq_ref PRIMARY PRIMARY 4 dbt3_s001.partsupp.ps_partkey 1 Using where
1 SIMPLE lineitem ref PRIMARY,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey,i_l_orderkey,i_l_orderkey_quantity i_l_suppkey_partkey 10 dbt3_s001.partsupp.ps_partkey,dbt3_s001.supplier.s_suppkey 8
1 SIMPLE orders eq_ref PRIMARY PRIMARY 4 dbt3_s001.lineitem.l_orderkey 1
select nation, o_year, sum(amount) as sum_profit
from (select n_name as nation,
extract(year from o_orderdate) as o_year,
l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount
from part, supplier, lineitem, partsupp, orders, nation
where s_suppkey = l_suppkey and ps_suppkey = l_suppkey
and ps_partkey = l_partkey and p_partkey = l_partkey
and o_orderkey = l_orderkey and s_nationkey = n_nationkey
and p_name like '%green%') as profit
group by nation, o_year
order by nation, o_year desc;
nation o_year sum_profit
ARGENTINA 1997 18247.873399999993
ARGENTINA 1996 7731.089399999995
ARGENTINA 1995 134490.5697
ARGENTINA 1994 36767.101500000004
ARGENTINA 1993 35857.08
ARGENTINA 1992 35740
ETHIOPIA 1998 2758.7801999999992
ETHIOPIA 1997 19419.294599999997
ETHIOPIA 1995 51231.87439999999
ETHIOPIA 1994 3578.9478999999974
ETHIOPIA 1992 1525.8234999999986
IRAN 1998 37817.229600000006
IRAN 1997 52643.77359999999
IRAN 1996 70143.7761
IRAN 1995 84094.58260000001
IRAN 1994 18140.925599999995
IRAN 1993 78655.1676
IRAN 1992 87142.23960000002
IRAQ 1998 22860.8082
IRAQ 1997 93676.24359999999
IRAQ 1996 45103.3242
IRAQ 1994 36010.728599999995
IRAQ 1993 33221.9399
IRAQ 1992 47755.05900000001
KENYA 1998 44194.831999999995
KENYA 1997 57578.36259999999
KENYA 1996 59195.90210000001
KENYA 1995 79262.6278
KENYA 1994 102360.66609999999
KENYA 1993 128422.0196
KENYA 1992 181517.2089
MOROCCO 1998 41797.823199999984
MOROCCO 1997 23685.801799999994
MOROCCO 1996 62115.19579999998
MOROCCO 1995 42442.64300000001
MOROCCO 1994 48655.878000000004
MOROCCO 1993 22926.744400000003
MOROCCO 1992 32239.8088
PERU 1998 86999.36459999997
PERU 1997 121110.41070000001
PERU 1996 177040.40759999995
PERU 1995 122247.94520000002
PERU 1994 88046.25329999998
PERU 1993 49379.813799999996
PERU 1992 80646.86050000001
UNITED KINGDOM 1998 50577.25560000001
UNITED KINGDOM 1997 114288.8605
UNITED KINGDOM 1996 147684.46480000002
UNITED KINGDOM 1995 225267.65759999998
UNITED KINGDOM 1994 140595.5864
UNITED KINGDOM 1993 322548.49210000003
UNITED KINGDOM 1992 67747.88279999999
UNITED STATES 1998 3957.0431999999996
UNITED STATES 1997 94729.5704
UNITED STATES 1996 79297.85670000002
UNITED STATES 1995 62201.23360000001
UNITED STATES 1994 43075.629899999985
UNITED STATES 1993 27168.486199999996
UNITED STATES 1992 34092.366
set @save_optimizer_switch=@@optimizer_switch;
set optimizer_switch='extended_keys=on';
EXPLAIN select o_orderkey, p_partkey
from part, lineitem, orders
where p_retailprice > 1100 and o_orderdate='1997-01-01'
and o_orderkey=l_orderkey and p_partkey=l_partkey;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE orders ref PRIMARY,i_o_orderdate i_o_orderdate 4 const 1
1 SIMPLE lineitem ref PRIMARY,i_l_suppkey_partkey,i_l_partkey,i_l_orderkey,i_l_orderkey_quantity PRIMARY 4 dbt3_s001.orders.o_orderkey 4 Using where
1 SIMPLE part eq_ref PRIMARY,i_p_retailprice PRIMARY 4 dbt3_s001.lineitem.l_partkey 1 Using where
select o_orderkey, p_partkey
from part, lineitem, orders
where p_retailprice > 1100 and o_orderdate='1997-01-01'
and o_orderkey=l_orderkey and p_partkey=l_partkey;
o_orderkey p_partkey
5895 200
set optimizer_switch=@save_optimizer_switch;
DROP DATABASE dbt3_s001;
use test;
#
# Bug mdev-473: ANALYZE table locked for write
#
set use_stat_tables='complementary';
create table t1 (i int);
lock table t1 write;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status Table is already up to date
alter table t1 add column a varchar(8);
drop table t1;
#
# Bug mdev-487: memory leak in ANALYZE with stat tables
#
SET use_stat_tables = 'preferably';
CREATE TABLE t1 (a INT);
INSERT INTO t1 VALUES (1),(2);
DELETE FROM t1 WHERE a=1;
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
DROP TABLE t1;
#
# Bug mdev-518: corrupted/missing statistical tables
#
CREATE TABLE t1 (i int) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1),(2);
FLUSH TABLE t1;
SET use_stat_tables='never';
EXPLAIN SELECT * FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
FLUSH TABLES;
SET use_stat_tables='preferably';
EXPLAIN SELECT * FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
DROP TABLE t1;
set use_stat_tables=@save_use_stat_tables;
#
# Bug mdev-5204: invalid impossible where after reading const tables
# when use_stat_tables = 'preferably'
#
set use_stat_tables = 'preferably';
CREATE TABLE t1 (id int PRIMARY KEY) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1),(2);
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
CREATE TABLE t2 (name char(3)) ENGINE=MyISAM;
ANALYZE TABLE t2;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status Table is already up to date
INSERT INTO t2 VALUES ('USA'),('AUS');
SELECT * FROM t1 STRAIGHT_JOIN t2 WHERE name IN ( 'AUS','YEM' ) AND id = 1;
id name
1 AUS
EXPLAIN
SELECT * FROM t1 STRAIGHT_JOIN t2 WHERE name IN ( 'AUS','YEM' ) AND id = 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 4 const 1 Using index
1 SIMPLE t2 ALL NULL NULL NULL NULL 0 Using where
ANALYZE TABLE t2;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status OK
SELECT * FROM t1 STRAIGHT_JOIN t2 WHERE name IN ( 'AUS','YEM' ) AND id = 1;
id name
1 AUS
EXPLAIN
SELECT * FROM t1 STRAIGHT_JOIN t2 WHERE name IN ( 'AUS','YEM' ) AND id = 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 4 const 1 Using index
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
DROP TABLE t1,t2;
#
# MDEV-7370: Server deadlocks on renaming a table for which persistent statistics exists
#
drop database if exists db1;
drop database if exists db1;
create database db1;
create database db2;
use db1;
#
# First, run the original testcase:
#
create table t1 (i int);
insert into t1 values (10),(20);
analyze table t1 persistent for all;
Table Op Msg_type Msg_text
db1.t1 analyze status Engine-independent statistics collected
db1.t1 analyze status OK
rename table t1 to db2.t1;
# Verify that stats in the old database are gone:
select * from mysql.column_stats where db_name='db1' and table_name='t1';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
select * from mysql.table_stats where db_name='db1' and table_name='t1';
db_name table_name cardinality
# Verify that stats are present in the new database:
select * from mysql.column_stats where db_name='db2' and table_name='t1';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
db2 t1 i 10 20 0.0000 4.0000 1.0000 0 NULL NULL
select * from mysql.table_stats where db_name='db2' and table_name='t1';
db_name table_name cardinality
db2 t1 2
#
# Now, try with more than one column and with indexes:
#
use test;
create table t1(a int primary key);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
use db1;
create table t2 (a int, b int, c int, key IDX1(a), key IDX2(a,b));
insert into t2 select a/10, a/2, a from test.t1;
analyze table t2 persistent for all;
Table Op Msg_type Msg_text
db1.t2 analyze status Engine-independent statistics collected
db1.t2 analyze status Table is already up to date
alter table t2 rename db2.t2;
# Verify that stats in the old database are gone:
select * from mysql.table_stats where db_name='db1' and table_name='t2';
db_name table_name cardinality
select * from mysql.column_stats where db_name='db1' and table_name='t2';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
select * from mysql.index_stats where db_name='db1' and table_name='t2';
db_name table_name index_name prefix_arity avg_frequency
# Verify that stats are present in the new database:
select * from mysql.table_stats where db_name='db2' and table_name='t2';
db_name table_name cardinality
db2 t2 10
select * from mysql.column_stats where db_name='db2' and table_name='t2';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
db2 t2 a 0 1 0.0000 4.0000 5.0000 0 NULL NULL
db2 t2 b 0 5 0.0000 4.0000 1.6667 0 NULL NULL
db2 t2 c 0 9 0.0000 4.0000 1.0000 0 NULL NULL
select * from mysql.index_stats where db_name='db2' and table_name='t2';
db_name table_name index_name prefix_arity avg_frequency
db2 t2 IDX1 1 5.0000
db2 t2 IDX2 1 5.0000
db2 t2 IDX2 2 1.6667
use db2;
#
# Now, rename within the same database and verify:
#
rename table t2 to t3;
# No stats under old name:
select * from mysql.table_stats where db_name='db2' and table_name='t2';
db_name table_name cardinality
select * from mysql.column_stats where db_name='db2' and table_name='t2';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
select * from mysql.index_stats where db_name='db2' and table_name='t2';
db_name table_name index_name prefix_arity avg_frequency
# Stats under the new name:
select * from mysql.table_stats where db_name='db2' and table_name='t3';
db_name table_name cardinality
db2 t3 10
select * from mysql.column_stats where db_name='db2' and table_name='t3';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
db2 t3 a 0 1 0.0000 4.0000 5.0000 0 NULL NULL
db2 t3 b 0 5 0.0000 4.0000 1.6667 0 NULL NULL
db2 t3 c 0 9 0.0000 4.0000 1.0000 0 NULL NULL
select * from mysql.index_stats where db_name='db2' and table_name='t3';
db_name table_name index_name prefix_arity avg_frequency
db2 t3 IDX1 1 5.0000
db2 t3 IDX2 1 5.0000
db2 t3 IDX2 2 1.6667
use test;
drop database db1;
drop database db2;
drop table t1;
#
# MDEV-16552: [10.0] ASAN global-buffer-overflow in is_stat_table / statistics_for_tables_is_needed
#
SET use_stat_tables = PREFERABLY;
SELECT CONVERT_TZ( '1991-09-20 10:11:02', '+00:00', 'GMT' );
CONVERT_TZ( '1991-09-20 10:11:02', '+00:00', 'GMT' )
NULL
set use_stat_tables=@save_use_stat_tables;
#
# MDEV-16757: manual addition of min/max statistics for BLOB
#
SET use_stat_tables= PREFERABLY;
CREATE TABLE t1 (pk INT PRIMARY KEY, t TEXT);
INSERT INTO t1 VALUES (1,'foo'),(2,'bar');
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze Warning Engine-independent statistics are not collected for column 't'
test.t1 analyze status OK
SELECT * FROM mysql.column_stats;
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
test t1 pk 1 2 0.0000 4.0000 1.0000 0 NULL NULL
DELETE FROM mysql.column_stats
WHERE db_name='test' AND table_name='t1' AND column_name='t';
INSERT INTO mysql.column_stats VALUES
('test','t1','t','bar','foo', 0.0, 3.0, 1.0, 0, NULL, NULL);
SELECT * FROM mysql.column_stats;
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
test t1 pk 1 2 0.0000 4.0000 1.0000 0 NULL NULL
test t1 t bar foo 0.0000 3.0000 1.0000 0 NULL NULL
SELECT pk FROM t1;
pk
1
2
DROP TABLE t1;
set use_stat_tables=@save_use_stat_tables;
#
# MDEV-16760: CREATE OR REPLACE TABLE after ANALYZE TABLE
#
SET use_stat_tables= PREFERABLY;
CREATE TABLE t1 (pk int PRIMARY KEY, c varchar(32));
INSERT INTO t1 VALUES (1,'foo'),(2,'bar');
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
SELECT * FROM t1;
pk c
1 foo
2 bar
SELECT * FROM mysql.column_stats;
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
test t1 pk 1 2 0.0000 4.0000 1.0000 0 NULL NULL
test t1 c bar foo 0.0000 3.0000 1.0000 0 NULL NULL
CREATE OR REPLACE TABLE t1 (pk int PRIMARY KEY, a char(7));
SELECT * FROM t1;
pk a
SELECT * FROM mysql.column_stats;
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
DROP TABLE t1;
set use_stat_tables=@save_use_stat_tables;
#
# MDEV-17023: Crash during read_histogram_for_table with optimizer_use_condition_selectivity set to 4
#
set @save_optimizer_use_condition_selectivity=@@optimizer_use_condition_selectivity;
set @@optimizer_use_condition_selectivity=4;
set @@use_stat_tables= PREFERABLY;
explain
SELECT * FROM INFORMATION_SCHEMA.PROFILING, mysql.user;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE PROFILING ALL NULL NULL NULL NULL NULL
1 SIMPLE user ALL NULL NULL NULL NULL 4 Using join buffer (flat, BNL join)
set @@optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@save_use_stat_tables;
#
# MDEV-17734: AddressSanitizer: use-after-poison in create_key_parts_for_pseudo_indexes
#
set @@use_stat_tables= PREFERABLY;
set @save_optimizer_use_condition_selectivity= @@optimizer_use_condition_selectivity;
set @@optimizer_use_condition_selectivity=4;
set @save_use_stat_tables= @@use_stat_tables;
create table t1 (a int, b int);
insert into t1(a,b) values (1,2),(1,3),(1,4),(1,5),(2,6),(2,7),(3,8),(3,9),(3,9),(4,10);
analyze table t1 persistent for columns (a) indexes ();
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
select * from t1 where a=1 and b=3;
a b
1 3
set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
set use_stat_tables=@save_use_stat_tables;
drop table t1;
#
# MDEV-16711:CREATE OR REPLACE TABLE introducing BLOB column
#
SET use_stat_tables= PREFERABLY;
CREATE TABLE t1 (pk INT PRIMARY KEY, t CHAR(60));
INSERT INTO t1 VALUES (1,'foo'),(2,'bar');
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
CREATE OR REPLACE TABLE t1 (pk INT PRIMARY KEY, t TEXT);
SELECT MAX(pk) FROM t1;
MAX(pk)
NULL
DROP TABLE t1;
#
# MDEV-17605: SHOW INDEXES with use_stat_tables='preferably'
#
set use_stat_tables='preferably';
CREATE DATABASE dbt3_s001;
use dbt3_s001;
set @save_optimizer_switch=@@optimizer_switch;
set optimizer_switch='extended_keys=off';
select * from mysql.table_stats;
db_name table_name cardinality
dbt3_s001 lineitem 6005
select * from mysql.index_stats;
db_name table_name index_name prefix_arity avg_frequency
dbt3_s001 lineitem PRIMARY 1 4.0033
dbt3_s001 lineitem PRIMARY 2 1.0000
dbt3_s001 lineitem i_l_shipdate 1 2.6500
dbt3_s001 lineitem i_l_suppkey_partkey 1 30.0250
dbt3_s001 lineitem i_l_suppkey_partkey 2 8.5786
dbt3_s001 lineitem i_l_partkey 1 30.0250
dbt3_s001 lineitem i_l_suppkey 1 600.5000
dbt3_s001 lineitem i_l_receiptdate 1 2.6477
dbt3_s001 lineitem i_l_orderkey 1 4.0033
dbt3_s001 lineitem i_l_orderkey_quantity 1 4.0033
dbt3_s001 lineitem i_l_orderkey_quantity 2 1.0404
dbt3_s001 lineitem i_l_commitdate 1 2.7160
SHOW INDEXES FROM lineitem;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
lineitem 0 PRIMARY 1 l_orderkey A 1500 NULL NULL BTREE
lineitem 0 PRIMARY 2 l_linenumber A 6005 NULL NULL BTREE
lineitem 1 i_l_shipdate 1 l_shipDATE A 2266 NULL NULL YES BTREE
lineitem 1 i_l_suppkey_partkey 1 l_partkey A 200 NULL NULL YES BTREE
lineitem 1 i_l_suppkey_partkey 2 l_suppkey A 699 NULL NULL YES BTREE
lineitem 1 i_l_partkey 1 l_partkey A 200 NULL NULL YES BTREE
lineitem 1 i_l_suppkey 1 l_suppkey A 10 NULL NULL YES BTREE
lineitem 1 i_l_receiptdate 1 l_receiptDATE A 2268 NULL NULL YES BTREE
lineitem 1 i_l_orderkey 1 l_orderkey A 1500 NULL NULL BTREE
lineitem 1 i_l_orderkey_quantity 1 l_orderkey A 1500 NULL NULL BTREE
lineitem 1 i_l_orderkey_quantity 2 l_quantity A 5771 NULL NULL YES BTREE
lineitem 1 i_l_commitdate 1 l_commitDATE A 2210 NULL NULL YES BTREE
SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE table_name='lineitem';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT INDEX_COMMENT
def dbt3_s001 lineitem 0 dbt3_s001 PRIMARY 1 l_orderkey A 1500 NULL NULL BTREE
def dbt3_s001 lineitem 0 dbt3_s001 PRIMARY 2 l_linenumber A 6005 NULL NULL BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_shipdate 1 l_shipDATE A 2266 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_suppkey_partkey 1 l_partkey A 200 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_suppkey_partkey 2 l_suppkey A 699 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_partkey 1 l_partkey A 200 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_suppkey 1 l_suppkey A 10 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_receiptdate 1 l_receiptDATE A 2268 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_orderkey 1 l_orderkey A 1500 NULL NULL BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_orderkey_quantity 1 l_orderkey A 1500 NULL NULL BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_orderkey_quantity 2 l_quantity A 5771 NULL NULL YES BTREE
def dbt3_s001 lineitem 1 dbt3_s001 i_l_commitdate 1 l_commitDATE A 2210 NULL NULL YES BTREE
SELECT
COUNT(DISTINCT l_orderkey), COUNT(DISTINCT l_orderkey,l_linenumber),
COUNT(DISTINCT l_shipDATE),
COUNT(DISTINCT l_partkey), COUNT(DISTINCT l_partkey,l_suppkey),
COUNT(DISTINCT l_suppkey), COUNT(DISTINCT l_receiptDATE),
COUNT(DISTINCT l_orderkey, l_quantity), COUNT(DISTINCT l_commitDATE)
FROM lineitem;
COUNT(DISTINCT l_orderkey) COUNT(DISTINCT l_orderkey,l_linenumber) COUNT(DISTINCT l_shipDATE) COUNT(DISTINCT l_partkey) COUNT(DISTINCT l_partkey,l_suppkey) COUNT(DISTINCT l_suppkey) COUNT(DISTINCT l_receiptDATE) COUNT(DISTINCT l_orderkey, l_quantity) COUNT(DISTINCT l_commitDATE)
1500 6005 2266 200 700 10 2268 5772 2211
set optimizer_switch=@save_optimizer_switch;
DROP DATABASE dbt3_s001;
USE test;
delete from mysql.table_stats;
delete from mysql.column_stats;
delete from mysql.index_stats;
#
# MDEV-19352: Server crash in alloc_histograms_for_table_share upon query from information schema
#
use test;
set @save_optimizer_use_condition_selectivity= @@optimizer_use_condition_selectivity;
set @@optimizer_use_condition_selectivity= 4;
set use_stat_tables='preferably';
CREATE TABLE t1 (a INT);
CREATE TABLE t2 (b INT);
CREATE VIEW v AS SELECT * FROM t1 JOIN t2;
INSERT INTO t2 SELECT * FROM x;
ERROR 42S02: Table 'test.x' doesn't exist
select * from information_schema.tables where table_name='v';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME TABLE_TYPE ENGINE VERSION ROW_FORMAT TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE AUTO_INCREMENT CREATE_TIME UPDATE_TIME CHECK_TIME TABLE_COLLATION CHECKSUM CREATE_OPTIONS TABLE_COMMENT MAX_INDEX_LENGTH TEMPORARY
def test v VIEW NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL VIEW NULL NULL
set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
drop table t1,t2;
drop view v;
#
# MDEV-19407: Assertion `field->table->stats_is_read' failed in is_eits_usable
#
set @save_optimizer_use_condition_selectivity= @@optimizer_use_condition_selectivity;
set @@optimizer_use_condition_selectivity= 1;
set @@use_stat_tables='never';
create table t1(pk int);
insert into t1 values (4),(3);
set @@optimizer_use_condition_selectivity= 4;
set use_stat_tables='preferably';
INSERT INTO t1 SELECT * FROM x;
ERROR 42S02: Table 'test.x' doesn't exist
CREATE TABLE t2 SELECT pk FROM t1 WHERE pk>2;
select * from t2;
pk
4
3
drop table t1,t2;
create table t1(a int,b int, key k1(a) );
insert into t1 values(1,1),(2,2),(3,3);
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
select * from mysql.index_stats, t1 where index_name='k1' and t1.a > 1 and t1.b > 1;
db_name table_name index_name prefix_arity avg_frequency a b
test t1 k1 1 1.0000 2 2
test t1 k1 1 1.0000 3 3
drop table t1;
set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
set @save_optimizer_switch=@@optimizer_switch;
set use_stat_tables=@save_use_stat_tables;
#
# MDEV-18899: Server crashes in Field::set_warning_truncated_wrong_value
#
set names utf8;
set @save_optimizer_use_condition_selectivity=@@optimizer_use_condition_selectivity;
set optimizer_use_condition_selectivity=4;
set use_stat_tables=preferably;
set histogram_size=255;
create table t1 ( a varchar(255) character set utf8);
insert into t1 values (REPEAT('ӥ',255)), (REPEAT('ç',255));
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
select HEX(RIGHT(min_value, 1)), length(min_value) from mysql.column_stats where db_name='test' and table_name='t1';
HEX(RIGHT(min_value, 1)) length(min_value)
A7 254
select HEX(RIGHT(max_value, 1)), length(max_value) from mysql.column_stats where db_name='test' and table_name='t1';
HEX(RIGHT(max_value, 1)) length(max_value)
A5 254
analyze select * from t1 where a >= 'ӥ';
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 2.00 50.00 50.00 Using where
set @save_sql_mode= @@sql_mode;
set sql_mode='ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';
update mysql.column_stats set min_value= REPEAT('ӥ',255) where db_name='test' and table_name='t1';
Warnings:
Warning 1265 Data truncated for column 'min_value' at row 1
select HEX(RIGHT(min_value, 1)), length(min_value) from mysql.column_stats where db_name='test' and table_name='t1';
HEX(RIGHT(min_value, 1)) length(min_value)
D3 255
analyze select * from t1 where a >= 'ӥ';
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 2.00 50.00 50.00 Using where
set names latin1;
drop table t1;
CREATE TABLE t1 (col1 date);
INSERT INTO t1 VALUES('2004-01-01'),('2004-02-29');
INSERT INTO t1 VALUES('0000-10-31');
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
update mysql.column_stats set min_value='2004-0-31123' where db_name='test' and table_name='t1';
select min_value from mysql.column_stats where db_name='test' and table_name='t1';
min_value
2004-0-31123
select * from t1;
col1
2004-01-01
2004-02-29
0000-10-31
set @@sql_mode= @save_sql_mode;
set use_stat_tables=@save_use_stat_tables;
set @@histogram_size= @save_histogram_size;
set @@optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
drop table t1;
#
# MDEV-20589: Server still crashes in Field::set_warning_truncated_wrong_value
#
set names utf8;
create table t1 ( a varchar(255) character set utf8);
insert into t1 values (REPEAT('ӥ',255)), (REPEAT('ç',255));
set use_stat_tables='preferably';
analyze table t1 persistent for all;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
set @save_sql_mode= @@sql_mode;
set sql_mode='ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';
update mysql.column_stats set min_value= REPEAT('ӥ',256) where db_name='test' and table_name='t1';
Warnings:
Warning 1265 Data truncated for column 'min_value' at row 1
set @@sql_mode= @save_sql_mode;
select length(a) from t1 where a=REPEAT('ӥ',255);
length(a)
510
set names latin1;
set @@use_stat_tables=@save_use_stat_tables;
drop table t1;
# please keep this at the last
set @@global.histogram_size=@save_histogram_size;
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