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|
#
# Bug#35842412 WHERE NOT IN with subquery is much slower on 8.1 than 5.7
#
CREATE TABLE t1( b_id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
val VARCHAR(100) NOT NULL, val_n VARCHAR(100),
KEY ix_val (val, b_id), KEY ix_val_n (val_n, b_id));
CREATE TABLE t2( a_id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
val VARCHAR(100) NOT NULL, val_n VARCHAR(100),
UNIQUE KEY ix_val (val), UNIQUE KEY ix_val_n (val_n));
INSERT INTO t1(val, val_n)
WITH RECURSIVE DataSource(num, c1, c2) AS (
SELECT 1, lpad(1,25,'0'), lpad(1,25,'0')
UNION ALL
SELECT num + 1, lpad(mod(num+1,30),25,'0'),
lpad(ELT(num%400 != 0, mod(num+1,30)), 25, '0')
FROM DataSource
WHERE num < 1000
)
SELECT c1, c2 from DataSource;
INSERT INTO t2(val, val_n)
WITH RECURSIVE DataSource(num, c1, c2) AS (
SELECT 1, lpad(1,25,'0'), lpad(1,25,'0')
UNION ALL
SELECT num + 1, lpad(num+1,25,'0'), lpad(ELT(num%13 != 0, num+1), 25, '0')
FROM DataSource
WHERE num < 30
)
SELECT c1, c2 from DataSource;
ANALYZE TABLE t1, t2;
Table Op Msg_type Msg_text
test.t1 analyze status OK
test.t2 analyze status OK
# Should use group skip scan on t1
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val);
EXPLAIN
-> Nested loop inner join (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row covering index lookup on t2 using ix_val (val=t1.val) (rows=1)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val FROM t1 WHERE EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val);
val
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val) GROUP BY val;
EXPLAIN
-> Nested loop inner join (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row covering index lookup on t2 using ix_val (val=t1.val) (rows=1)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT val FROM t1 WHERE EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val) GROUP BY val;
val
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE val IN (SELECT val FROM t2);
EXPLAIN
-> Nested loop inner join (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row covering index lookup on t2 using ix_val (val=t1.val) (rows=1)
SELECT DISTINCT val FROM t1 WHERE val IN (SELECT val FROM t2);
val
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE val IN
(SELECT val FROM t2 WHERE t2.val = t1.val);
EXPLAIN
-> Nested loop inner join (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row covering index lookup on t2 using ix_val (val=t1.val) (rows=1)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val FROM t1 WHERE val IN
(SELECT val FROM t2 WHERE t2.val = t1.val);
val
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE val IN (SELECT val FROM t2 ) GROUP BY val;
EXPLAIN
-> Nested loop inner join (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row covering index lookup on t2 using ix_val (val=t1.val) (rows=1)
SELECT val FROM t1 WHERE val IN (SELECT val FROM t2 ) GROUP BY val;
val
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE val IN
(SELECT val FROM t2 WHERE t2.val = t1.val ) GROUP BY val;
EXPLAIN
-> Nested loop inner join (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row covering index lookup on t2 using ix_val (val=t1.val) (rows=1)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT val FROM t1 WHERE val IN
(SELECT val FROM t2 WHERE t2.val = t1.val ) GROUP BY val;
val
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val = 'asd');
EXPLAIN
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
SELECT DISTINCT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val = 'asd');
val
0000000000000000000000000
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val = 'asd' ) GROUP BY val;
EXPLAIN
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
SELECT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val = 'asd' ) GROUP BY val;
val
0000000000000000000000000
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
# Should use group skip scan on t1
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE val NOT IN (SELECT val FROM t2);
EXPLAIN
-> Nested loop antijoin (rows=930)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val is not null) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
SELECT DISTINCT val FROM t1 WHERE val NOT IN (SELECT val FROM t2);
val
0000000000000000000000000
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE val NOT IN
(SELECT val FROM t2 WHERE t2.val = t1.val);
EXPLAIN
-> Nested loop antijoin (rows=930)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val, val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: ((t2.val is not null) and (t2.val is not null)) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val FROM t1 WHERE val NOT IN
(SELECT val FROM t2 WHERE t2.val = t1.val);
val
0000000000000000000000000
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE val NOT IN
(SELECT val FROM t2 ) GROUP BY val;
EXPLAIN
-> Nested loop antijoin (rows=930)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val is not null) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
SELECT val FROM t1 WHERE val NOT IN
(SELECT val FROM t2 ) GROUP BY val;
val
0000000000000000000000000
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE val NOT IN
(SELECT val FROM t2 WHERE t2.val = t1.val ) GROUP BY val;
EXPLAIN
-> Nested loop antijoin (rows=930)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val, val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: ((t2.val is not null) and (t2.val is not null)) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT val FROM t1 WHERE val NOT IN
(SELECT val FROM t2 WHERE t2.val = t1.val ) GROUP BY val;
val
0000000000000000000000000
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val);
EXPLAIN
-> Nested loop antijoin (rows=930)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val is not null) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val);
val
0000000000000000000000000
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val) GROUP BY val;
EXPLAIN
-> Nested loop antijoin (rows=930)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val is not null) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
Warnings:
Note 1276 Field or reference 'test.t1.val' of SELECT #2 was resolved in SELECT #1
SELECT val FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val = t1.val) GROUP BY val;
val
0000000000000000000000000
# Should use group skip scan on t1
EXPLAIN FORMAT=TREE SELECT DISTINCT val FROM t1 WHERE EXISTS (SELECT * FROM t2);
EXPLAIN
-> Table scan on <temporary> (rows=31)
-> Temporary table with deduplication (rows=31)
-> Inner hash join (no condition) (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Hash
-> Limit: 1 row(s) (rows=1)
-> Index scan on t2 using ix_val (rows=30)
SELECT DISTINCT val FROM t1 WHERE EXISTS (SELECT * FROM t2);
val
0000000000000000000000000
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT val FROM t1 WHERE EXISTS (SELECT * FROM t2) GROUP BY val;
EXPLAIN
-> Table scan on <temporary> (rows=31)
-> Temporary table with deduplication (rows=31)
-> Inner hash join (no condition) (rows=31)
-> Covering index skip scan for deduplication on t1 using ix_val (rows=31)
-> Hash
-> Limit: 1 row(s) (rows=1)
-> Index scan on t2 using ix_val (rows=30)
SELECT val FROM t1 WHERE EXISTS (SELECT * FROM t2) GROUP BY val;
val
0000000000000000000000000
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
# Uses group skip scan with aggregate functions since "t2" is a const
# table. Hypergraph optimizer does not support const table optimization.
# So the plan chosen is different.
EXPLAIN FORMAT=TREE SELECT val, MIN(b_id), MAX(b_id) FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val = 'asd') GROUP BY val;
EXPLAIN
-> Covering index skip scan for grouping on t1 using ix_val (rows=31)
SELECT val, MIN(b_id), MAX(b_id) FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val = 'asd') GROUP BY val;
val MIN(b_id) MAX(b_id)
0000000000000000000000000 30 990
0000000000000000000000001 1 991
0000000000000000000000002 2 992
0000000000000000000000003 3 993
0000000000000000000000004 4 994
0000000000000000000000005 5 995
0000000000000000000000006 6 996
0000000000000000000000007 7 997
0000000000000000000000008 8 998
0000000000000000000000009 9 999
0000000000000000000000010 10 1000
0000000000000000000000011 11 971
0000000000000000000000012 12 972
0000000000000000000000013 13 973
0000000000000000000000014 14 974
0000000000000000000000015 15 975
0000000000000000000000016 16 976
0000000000000000000000017 17 977
0000000000000000000000018 18 978
0000000000000000000000019 19 979
0000000000000000000000020 20 980
0000000000000000000000021 21 981
0000000000000000000000022 22 982
0000000000000000000000023 23 983
0000000000000000000000024 24 984
0000000000000000000000025 25 985
0000000000000000000000026 26 986
0000000000000000000000027 27 987
0000000000000000000000028 28 988
0000000000000000000000029 29 989
# Should not use group skip scan on t1. Group skip scan is not supported
# on multi-table queries with aggregate functions.
EXPLAIN FORMAT=TREE SELECT val, MIN(b_id), MAX(b_id) FROM t1 WHERE val
NOT IN (SELECT val FROM t2) GROUP BY val;
EXPLAIN
-> Group aggregate: min(t1.b_id), max(t1.b_id) (rows=30)
-> Nested loop antijoin (rows=30000)
-> Index scan on t1 using ix_val (rows=1000)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val=t1.val) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val is not null) (rows=30)
-> Index scan on t2 using ix_val (rows=30)
SELECT val, MIN(b_id), MAX(b_id) FROM t1 WHERE val
NOT IN (SELECT val FROM t2) GROUP BY val;
val MIN(b_id) MAX(b_id)
0000000000000000000000000 30 990
EXPLAIN FORMAT=TREE SELECT val, MIN(b_id), MAX(b_id) FROM t1 WHERE EXISTS
(SELECT * FROM t2) GROUP BY val;
EXPLAIN
-> Table scan on <temporary>
-> Aggregate using temporary table
-> Inner hash join (no condition) (rows=1000)
-> Index scan on t1 using ix_val (rows=1000)
-> Hash
-> Limit: 1 row(s) (rows=1)
-> Index scan on t2 using ix_val (rows=30)
SELECT val, MIN(b_id), MAX(b_id) FROM t1 WHERE EXISTS
(SELECT * FROM t2) GROUP BY val;
val MIN(b_id) MAX(b_id)
0000000000000000000000000 30 990
0000000000000000000000001 1 991
0000000000000000000000002 2 992
0000000000000000000000003 3 993
0000000000000000000000004 4 994
0000000000000000000000005 5 995
0000000000000000000000006 6 996
0000000000000000000000007 7 997
0000000000000000000000008 8 998
0000000000000000000000009 9 999
0000000000000000000000010 10 1000
0000000000000000000000011 11 971
0000000000000000000000012 12 972
0000000000000000000000013 13 973
0000000000000000000000014 14 974
0000000000000000000000015 15 975
0000000000000000000000016 16 976
0000000000000000000000017 17 977
0000000000000000000000018 18 978
0000000000000000000000019 19 979
0000000000000000000000020 20 980
0000000000000000000000021 21 981
0000000000000000000000022 22 982
0000000000000000000000023 23 983
0000000000000000000000024 24 984
0000000000000000000000025 25 985
0000000000000000000000026 26 986
0000000000000000000000027 27 987
0000000000000000000000028 28 988
0000000000000000000000029 29 989
# Cover nullable column scenarios
# Should use group skip scan on t1
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE EXISTS
(SELECT * FROM t2 WHERE t2.val_n = t1.val_n);
EXPLAIN
-> Nested loop inner join (rows=32)
-> Filter: (t1.val_n is not null) (rows=32)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Single-row covering index lookup on t2 using ix_val_n (val_n=t1.val_n) (rows=1)
Warnings:
Note 1276 Field or reference 'test.t1.val_n' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val_n FROM t1 WHERE EXISTS
(SELECT * FROM t2 WHERE t2.val_n = t1.val_n);
val_n
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE val_n IN (SELECT val_n FROM t2);
EXPLAIN
-> Nested loop inner join (rows=32)
-> Filter: (t1.val_n is not null) (rows=32)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Single-row covering index lookup on t2 using ix_val_n (val_n=t1.val_n) (rows=1)
SELECT DISTINCT val_n FROM t1 WHERE val_n IN (SELECT val_n FROM t2);
val_n
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000028
0000000000000000000000029
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val_n = 'asd');
EXPLAIN
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
SELECT DISTINCT val_n FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val_n = 'asd');
val_n
NULL
0000000000000000000000000
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
# Should use group skip scan on t1
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE val_n NOT IN
(SELECT val_n FROM t2);
EXPLAIN
-> Filter: <in_optimizer>(t1.val_n,t1.val_n in (select #2) is false) (rows=32)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Select #2 (subquery in condition; run only once)
-> Filter: ((t1.val_n = `<materialized_subquery>`.val_n)) (rows=1)
-> Limit: 1 row(s) (rows=1)
-> Index lookup on <materialized_subquery> using <auto_distinct_key> (val_n=t1.val_n)
-> Materialize with deduplication (rows=30)
-> Index scan on t2 using ix_val_n (rows=30)
SELECT DISTINCT val_n FROM t1 WHERE val_n NOT IN
(SELECT val_n FROM t2);
val_n
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE val_n NOT IN
(SELECT val_n FROM t2 WHERE t2.val_n = t1.val_n);
EXPLAIN
-> Filter: <in_optimizer>(t1.val_n,<exists>(select #2) is false) (rows=32)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Select #2 (subquery in condition; dependent)
-> Limit: 1 row(s) (rows=1)
-> Filter: <if>(outer_field_is_not_null, <is_not_null_test>(t2.val_n), true) (rows=1)
-> Filter: <if>(outer_field_is_not_null, ((<cache>(t1.val_n) = t2.val_n) or (t2.val_n is null)), true) (rows=1)
-> Single-row covering index lookup on t2 using ix_val_n (val_n=t1.val_n) (rows=1)
Warnings:
Note 1276 Field or reference 'test.t1.val_n' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val_n FROM t1 WHERE val_n NOT IN
(SELECT val_n FROM t2 WHERE t2.val_n = t1.val_n);
val_n
NULL
0000000000000000000000000
0000000000000000000000014
0000000000000000000000027
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val_n = t1.val_n);
EXPLAIN
-> Nested loop antijoin (rows=960)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val_n=t1.val_n) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val_n is not null) (rows=30)
-> Index scan on t2 using ix_val_n (rows=30)
Warnings:
Note 1276 Field or reference 'test.t1.val_n' of SELECT #2 was resolved in SELECT #1
SELECT DISTINCT val_n FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val_n = t1.val_n);
val_n
NULL
0000000000000000000000000
0000000000000000000000014
0000000000000000000000027
EXPLAIN FORMAT=TREE SELECT val_n FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val_n = t1.val_n) GROUP BY val_n;
EXPLAIN
-> Nested loop antijoin (rows=960)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Single-row index lookup on <subquery2> using <auto_distinct_key> (val_n=t1.val_n) (rows=1)
-> Materialize with deduplication (rows=30)
-> Filter: (t2.val_n is not null) (rows=30)
-> Index scan on t2 using ix_val_n (rows=30)
Warnings:
Note 1276 Field or reference 'test.t1.val_n' of SELECT #2 was resolved in SELECT #1
SELECT val_n FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE t2.val_n = t1.val_n) GROUP BY val_n;
val_n
NULL
0000000000000000000000000
0000000000000000000000014
0000000000000000000000027
# Should use group skip scan on t1
EXPLAIN FORMAT=TREE SELECT DISTINCT val_n FROM t1 WHERE EXISTS (SELECT * FROM t2);
EXPLAIN
-> Table scan on <temporary> (rows=32)
-> Temporary table with deduplication (rows=32)
-> Inner hash join (no condition) (rows=32)
-> Covering index skip scan for deduplication on t1 using ix_val_n (rows=32)
-> Hash
-> Limit: 1 row(s) (rows=1)
-> Index scan on t2 using ix_val (rows=30)
SELECT DISTINCT val_n FROM t1 WHERE EXISTS (SELECT * FROM t2);
val_n
NULL
0000000000000000000000000
0000000000000000000000001
0000000000000000000000002
0000000000000000000000003
0000000000000000000000004
0000000000000000000000005
0000000000000000000000006
0000000000000000000000007
0000000000000000000000008
0000000000000000000000009
0000000000000000000000010
0000000000000000000000011
0000000000000000000000012
0000000000000000000000013
0000000000000000000000014
0000000000000000000000015
0000000000000000000000016
0000000000000000000000017
0000000000000000000000018
0000000000000000000000019
0000000000000000000000020
0000000000000000000000021
0000000000000000000000022
0000000000000000000000023
0000000000000000000000024
0000000000000000000000025
0000000000000000000000026
0000000000000000000000027
0000000000000000000000028
0000000000000000000000029
# Uses group skip scan with aggregate functions since "t2" is a const
# table. Hypergraph optimizer does not support const table optimization.
# So the plan chosen is different.
EXPLAIN FORMAT=TREE SELECT val_n, MIN(b_id), MAX(b_id) FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val_n = 'asd') GROUP BY val_n;
EXPLAIN
-> Covering index skip scan for grouping on t1 using ix_val_n (rows=32)
SELECT val_n, MIN(b_id), MAX(b_id) FROM t1 WHERE NOT EXISTS
(SELECT * FROM t2 WHERE val_n = 'asd') GROUP BY val_n;
val_n MIN(b_id) MAX(b_id)
NULL 401 801
0000000000000000000000000 30 990
0000000000000000000000001 1 991
0000000000000000000000002 2 992
0000000000000000000000003 3 993
0000000000000000000000004 4 994
0000000000000000000000005 5 995
0000000000000000000000006 6 996
0000000000000000000000007 7 997
0000000000000000000000008 8 998
0000000000000000000000009 9 999
0000000000000000000000010 10 1000
0000000000000000000000011 11 971
0000000000000000000000012 12 972
0000000000000000000000013 13 973
0000000000000000000000014 14 974
0000000000000000000000015 15 975
0000000000000000000000016 16 976
0000000000000000000000017 17 977
0000000000000000000000018 18 978
0000000000000000000000019 19 979
0000000000000000000000020 20 980
0000000000000000000000021 21 981
0000000000000000000000022 22 982
0000000000000000000000023 23 983
0000000000000000000000024 24 984
0000000000000000000000025 25 985
0000000000000000000000026 26 986
0000000000000000000000027 27 987
0000000000000000000000028 28 988
0000000000000000000000029 29 989
# Should not use group skip scan on t1. Group skip scan is not supported
# on multi-table queries with aggregate functions.
EXPLAIN FORMAT=TREE SELECT val_n, MIN(b_id), MAX(b_id) FROM t1 WHERE val_n
NOT IN (SELECT val_n FROM t2) GROUP BY val_n;
EXPLAIN
-> Group aggregate: min(t1.b_id), max(t1.b_id) (rows=31)
-> Filter: <in_optimizer>(t1.val_n,t1.val_n in (select #2) is false) (rows=1000)
-> Index scan on t1 using ix_val_n (rows=1000)
-> Select #2 (subquery in condition; run only once)
-> Filter: ((t1.val_n = `<materialized_subquery>`.val_n)) (rows=1)
-> Limit: 1 row(s) (rows=1)
-> Index lookup on <materialized_subquery> using <auto_distinct_key> (val_n=t1.val_n)
-> Materialize with deduplication (rows=30)
-> Index scan on t2 using ix_val_n (rows=30)
SELECT val_n, MIN(b_id), MAX(b_id) FROM t1 WHERE val_n
NOT IN (SELECT val_n FROM t2) GROUP BY val_n;
val_n MIN(b_id) MAX(b_id)
EXPLAIN FORMAT=TREE SELECT val_n, MIN(b_id), MAX(b_id) FROM t1 WHERE EXISTS
(SELECT * FROM t2) GROUP BY val_n;
EXPLAIN
-> Table scan on <temporary>
-> Aggregate using temporary table
-> Inner hash join (no condition) (rows=1000)
-> Index scan on t1 using ix_val_n (rows=1000)
-> Hash
-> Limit: 1 row(s) (rows=1)
-> Index scan on t2 using ix_val (rows=30)
SELECT val_n, MIN(b_id), MAX(b_id) FROM t1 WHERE EXISTS
(SELECT * FROM t2) GROUP BY val_n;
val_n MIN(b_id) MAX(b_id)
NULL 401 801
0000000000000000000000000 30 990
0000000000000000000000001 1 991
0000000000000000000000002 2 992
0000000000000000000000003 3 993
0000000000000000000000004 4 994
0000000000000000000000005 5 995
0000000000000000000000006 6 996
0000000000000000000000007 7 997
0000000000000000000000008 8 998
0000000000000000000000009 9 999
0000000000000000000000010 10 1000
0000000000000000000000011 11 971
0000000000000000000000012 12 972
0000000000000000000000013 13 973
0000000000000000000000014 14 974
0000000000000000000000015 15 975
0000000000000000000000016 16 976
0000000000000000000000017 17 977
0000000000000000000000018 18 978
0000000000000000000000019 19 979
0000000000000000000000020 20 980
0000000000000000000000021 21 981
0000000000000000000000022 22 982
0000000000000000000000023 23 983
0000000000000000000000024 24 984
0000000000000000000000025 25 985
0000000000000000000000026 26 986
0000000000000000000000027 27 987
0000000000000000000000028 28 988
0000000000000000000000029 29 989
DROP TABLE t1, t2;
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