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|
DROP TABLE IF EXISTS t1,t2,t3,t4;
DROP DATABASE IF EXISTS world;
set names utf8;
CREATE DATABASE world;
use world;
CREATE TABLE Country (
Code char(3) NOT NULL default '',
Name char(52) NOT NULL default '',
SurfaceArea float(10,2) NOT NULL default '0.00',
Population int(11) NOT NULL default '0',
Capital int(11) default NULL,
PRIMARY KEY (Code),
UNIQUE INDEX (Name)
);
CREATE TABLE City (
ID int(11) NOT NULL auto_increment,
Name char(35) NOT NULL default '',
Country char(3) NOT NULL default '',
Population int(11) NOT NULL default '0',
PRIMARY KEY (ID),
INDEX (Population),
INDEX (Country)
);
CREATE TABLE CountryLanguage (
Country char(3) NOT NULL default '',
Language char(30) NOT NULL default '',
Percentage float(3,1) NOT NULL default '0.0',
PRIMARY KEY (Country, Language),
INDEX (Percentage)
);
SELECT COUNT(*) FROM Country;
COUNT(*)
239
SELECT COUNT(*) FROM City;
COUNT(*)
4079
SELECT COUNT(*) FROM CountryLanguage;
COUNT(*)
984
CREATE INDEX Name ON City(Name);
set session optimizer_switch='index_merge_sort_intersection=off';
EXPLAIN
SELECT * FROM City
WHERE (Population >= 100000 OR Name LIKE 'P%' OR Population < 100000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Population,Name NULL NULL NULL 4079 Using where
EXPLAIN
SELECT * FROM City
WHERE (Population >= 100000 OR Name LIKE 'P%') AND Country='CAN' OR
(Population < 100000 OR Name Like 'T%') AND Country='ARG';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population,Country,Name Country 3 NULL 104 Using index condition; Using where
EXPLAIN
SELECT * FROM City
WHERE Population < 200000 AND Name LIKE 'P%' AND
(Population > 300000 OR Name LIKE 'T%') AND
(Population < 100000 OR Name LIKE 'Pa%');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population,Name Name 35 NULL 135 Using index condition; Using where
EXPLAIN
SELECT * FROM City
WHERE Population > 100000 AND Name LIKE 'Aba%' OR
Country IN ('CAN', 'ARG') AND ID BETWEEN 120 AND 130 OR
Country <= 'ALB' AND Name LIKE 'L%' OR
ID BETWEEN 3807 AND 3810;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name Name,PRIMARY,Country 35,4,3 NULL 30 Using sort_union(Name,PRIMARY,Country); Using where
EXPLAIN
SELECT * FROM City
WHERE (Population > 101000 AND Population < 115000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 459 Using index condition
EXPLAIN
SELECT * FROM City
WHERE (Population > 101000 AND Population < 102000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 39 Using index condition
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Country,Name Name,Country 35,3 NULL 172 Using sort_union(Name,Country); Using where
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'))
AND (Population > 101000 AND Population < 115000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Population,Country,Name Name,Country 35,3 NULL 172 Using sort_union(Name,Country); Using where
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'))
AND (Population > 101000 AND Population < 102000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population,Country,Name Population 4 NULL 39 Using index condition; Using where
SELECT * FROM City USE INDEX ()
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'))
AND (Population > 101000 AND Population < 115000);
ID Name Country Population
403 Catanduva BRA 107761
412 Cachoeirinha BRA 103240
636 Bilbays EGY 113608
637 Mit Ghamr EGY 101801
701 Tarragona ESP 113016
702 Lleida (Lérida) ESP 112207
703 Jaén ESP 109247
704 Ourense (Orense) ESP 109120
705 Mataró ESP 104095
706 Algeciras ESP 103106
707 Marbella ESP 101144
759 Gonder ETH 112249
869 Cabuyao PHL 106630
870 Calapan PHL 105910
873 Cauayan PHL 103952
1844 Cape Breton CAN 114733
1847 Cambridge CAN 109186
2908 Cajamarca PER 108009
3003 Caen FRA 113987
3411 Ceyhan TUR 102412
3571 Calabozo VEN 107146
3786 Cam Ranh VNM 114041
3792 Tartu EST 101246
4002 Carrollton USA 109576
4027 Cape Coral USA 102286
4032 Cambridge USA 101355
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'))
AND (Population > 101000 AND Population < 115000);
ID Name Country Population
403 Catanduva BRA 107761
412 Cachoeirinha BRA 103240
636 Bilbays EGY 113608
637 Mit Ghamr EGY 101801
701 Tarragona ESP 113016
702 Lleida (Lérida) ESP 112207
703 Jaén ESP 109247
704 Ourense (Orense) ESP 109120
705 Mataró ESP 104095
706 Algeciras ESP 103106
707 Marbella ESP 101144
759 Gonder ETH 112249
869 Cabuyao PHL 106630
870 Calapan PHL 105910
873 Cauayan PHL 103952
1844 Cape Breton CAN 114733
1847 Cambridge CAN 109186
2908 Cajamarca PER 108009
3003 Caen FRA 113987
3411 Ceyhan TUR 102412
3571 Calabozo VEN 107146
3786 Cam Ranh VNM 114041
3792 Tartu EST 101246
4002 Carrollton USA 109576
4027 Cape Coral USA 102286
4032 Cambridge USA 101355
SELECT * FROM City USE INDEX ()
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'))
AND (Population > 101000 AND Population < 102000);
ID Name Country Population
637 Mit Ghamr EGY 101801
707 Marbella ESP 101144
3792 Tartu EST 101246
4032 Cambridge USA 101355
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'F'))
AND (Population > 101000 AND Population < 102000);
ID Name Country Population
707 Marbella ESP 101144
3792 Tartu EST 101246
4032 Cambridge USA 101355
637 Mit Ghamr EGY 101801
EXPLAIN
SELECT * FROM City WHERE (Name < 'Ac');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 13 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Name < 'Bb');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 207 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Country > 'A' AND Country < 'B');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country Country 3 NULL 104 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Name BETWEEN 'P' AND 'Pb');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 39 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Name BETWEEN 'P' AND 'S');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 221 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Population > 101000 AND Population < 110000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 328 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Population > 103000 AND Population < 104000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 37 Using index condition
EXPLAIN
SELECT * FROM City
WHERE (Name < 'Ac' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'Pb' AND (Population > 101000 AND Population < 110000));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population,Country,Name Name 35 NULL 52 Using index condition; Using where
EXPLAIN
SELECT * FROM City
WHERE (Name < 'Ac' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'S' AND (Population > 103000 AND Population < 104000));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Population,Country,Name Name,Population 35,4 NULL 50 Using sort_union(Name,Population); Using where
EXPLAIN
SELECT * FROM City
WHERE (Name < 'Bb' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'Pb' AND (Population > 101000 AND Population < 110000));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Population,Country,Name Country,Name 3,35 NULL 143 Using sort_union(Country,Name); Using where
EXPLAIN
SELECT * FROM City
WHERE (Name < 'Bb' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'S' AND (Population > 103000 AND Population < 104000));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Population,Country,Name Country,Population 3,4 NULL 141 Using sort_union(Country,Population); Using where
SELECT * FROM City USE INDEX ()
WHERE (Name < 'Ac' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'Pb' AND (Population > 101000 AND Population < 110000));
ID Name Country Population
65 Abu Dhabi ARE 398695
168 Pabna BGD 103277
189 Parakou BEN 103577
750 Paarl ZAF 105768
2865 Pak Pattan PAK 107800
SELECT * FROM City
WHERE (Name < 'Ac' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'Pb' AND (Population > 101000 AND Population < 110000));
ID Name Country Population
65 Abu Dhabi ARE 398695
750 Paarl ZAF 105768
168 Pabna BGD 103277
2865 Pak Pattan PAK 107800
189 Parakou BEN 103577
SELECT * FROM City USE INDEX ()
WHERE (Name < 'Ac' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'S' AND (Population > 103000 AND Population < 104000));
ID Name Country Population
65 Abu Dhabi ARE 398695
168 Pabna BGD 103277
189 Parakou BEN 103577
1003 Pemalang IDN 103500
2663 Río Bravo MEX 103901
SELECT * FROM City
WHERE (Name < 'Ac' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'S' AND (Population > 103000 AND Population < 104000));
ID Name Country Population
65 Abu Dhabi ARE 398695
168 Pabna BGD 103277
189 Parakou BEN 103577
1003 Pemalang IDN 103500
2663 Río Bravo MEX 103901
SELECT * FROM City USE INDEX ()
WHERE (Name < 'Bb' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'Pb' AND (Population > 101000 AND Population < 110000));
ID Name Country Population
55 Andorra la Vella AND 21189
65 Abu Dhabi ARE 398695
67 al-Ayn ARE 225970
68 Ajman ARE 114395
75 Almirante Brown ARG 538918
85 Avellaneda ARG 353046
96 Bahía Blanca ARG 239810
134 Adelaide AUS 978100
144 Baku AZE 1787800
168 Pabna BGD 103277
189 Parakou BEN 103577
750 Paarl ZAF 105768
2865 Pak Pattan PAK 107800
SELECT * FROM City
WHERE (Name < 'Bb' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'Pb' AND (Population > 101000 AND Population < 110000));
ID Name Country Population
55 Andorra la Vella AND 21189
65 Abu Dhabi ARE 398695
67 al-Ayn ARE 225970
68 Ajman ARE 114395
75 Almirante Brown ARG 538918
85 Avellaneda ARG 353046
96 Bahía Blanca ARG 239810
134 Adelaide AUS 978100
144 Baku AZE 1787800
168 Pabna BGD 103277
189 Parakou BEN 103577
750 Paarl ZAF 105768
2865 Pak Pattan PAK 107800
SELECT * FROM City USE INDEX ()
WHERE (Name < 'Bb' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'S' AND (Population > 103000 AND Population < 104000));
ID Name Country Population
55 Andorra la Vella AND 21189
65 Abu Dhabi ARE 398695
67 al-Ayn ARE 225970
68 Ajman ARE 114395
75 Almirante Brown ARG 538918
85 Avellaneda ARG 353046
96 Bahía Blanca ARG 239810
134 Adelaide AUS 978100
144 Baku AZE 1787800
168 Pabna BGD 103277
189 Parakou BEN 103577
1003 Pemalang IDN 103500
2663 Río Bravo MEX 103901
SELECT * FROM City
WHERE (Name < 'Bb' AND (Country > 'A' AND Country < 'B')) OR
(Name BETWEEN 'P' AND 'S' AND (Population > 103000 AND Population < 104000));
ID Name Country Population
55 Andorra la Vella AND 21189
65 Abu Dhabi ARE 398695
67 al-Ayn ARE 225970
68 Ajman ARE 114395
75 Almirante Brown ARG 538918
85 Avellaneda ARG 353046
96 Bahía Blanca ARG 239810
134 Adelaide AUS 978100
144 Baku AZE 1787800
168 Pabna BGD 103277
189 Parakou BEN 103577
1003 Pemalang IDN 103500
2663 Río Bravo MEX 103901
EXPLAIN
SELECT * FROM City WHERE (ID < 10) OR (ID BETWEEN 100 AND 110);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 20 Using index condition
EXPLAIN
SELECT * FROM City WHERE (ID < 200) OR (ID BETWEEN 100 AND 200);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 200 Using index condition
EXPLAIN
SELECT * FROM City WHERE (ID < 600) OR (ID BETWEEN 900 AND 1500);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL PRIMARY NULL NULL NULL 4079 Using where
EXPLAIN
SELECT * FROM City WHERE Country > 'A' AND Country < 'ARG';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country Country 3 NULL 20 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name LIKE 'H%' OR Name LIKE 'P%' ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 223 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name LIKE 'Ha%' OR Name LIKE 'Pa%' ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 72 Using index condition
EXPLAIN
SELECT * FROM City
WHERE ((ID < 10) AND (Name LIKE 'H%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 100 AND 110) AND
(Name LIKE 'P%' OR (Population > 103000 AND Population < 104000)));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY,Population,Country,Name PRIMARY 4 NULL 20 Using index condition; Using where
EXPLAIN
SELECT * FROM City
WHERE ((ID < 800) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 900 AND 1500) AND
(Name LIKE 'Pa%' OR (Population > 103000 AND Population < 105000)));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name Name,Country,Population 35,3,4 NULL 151 Using sort_union(Name,Country,Population); Using where
EXPLAIN
SELECT * FROM City
WHERE ((ID < 200) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 100 AND 200) AND
(Name LIKE 'Pa%' OR (Population > 103200 AND Population < 104000)));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name Name,Country,Population 35,3,4 NULL 124 Using sort_union(Name,Country,Population); Using where
SELECT * FROM City USE INDEX ()
WHERE ((ID < 10) AND (Name LIKE 'H%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 100 AND 110) AND
(Name LIKE 'P%' OR (Population > 103000 AND Population < 104000)));
ID Name Country Population
1 Kabul AFG 1780000
2 Qandahar AFG 237500
3 Herat AFG 186800
4 Mazar-e-Sharif AFG 127800
7 Haag NLD 440900
100 Paraná ARG 207041
102 Posadas ARG 201273
SELECT * FROM City
WHERE ((ID < 10) AND (Name LIKE 'H%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 100 AND 110) AND
(Name LIKE 'P%' OR (Population > 103000 AND Population < 104000)));
ID Name Country Population
1 Kabul AFG 1780000
2 Qandahar AFG 237500
3 Herat AFG 186800
4 Mazar-e-Sharif AFG 127800
7 Haag NLD 440900
100 Paraná ARG 207041
102 Posadas ARG 201273
SELECT * FROM City USE INDEX()
WHERE ((ID < 800) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 900 AND 1500) AND
(Name LIKE 'Pa%' OR (Population > 103000 AND Population < 104000)));
ID Name Country Population
1 Kabul AFG 1780000
2 Qandahar AFG 237500
3 Herat AFG 186800
4 Mazar-e-Sharif AFG 127800
7 Haag NLD 440900
16 Haarlem NLD 148772
25 Haarlemmermeer NLD 110722
33 Willemstad ANT 2345
34 Tirana ALB 270000
55 Andorra la Vella AND 21189
56 Luanda AGO 2022000
57 Huambo AGO 163100
58 Lobito AGO 130000
59 Benguela AGO 128300
60 Namibe AGO 118200
61 South Hill AIA 961
62 The Valley AIA 595
64 Dubai ARE 669181
65 Abu Dhabi ARE 398695
66 Sharja ARE 320095
67 al-Ayn ARE 225970
68 Ajman ARE 114395
129 Oranjestad ABW 29034
191 Hamilton BMU 1200
528 Hartlepool GBR 92000
529 Halifax GBR 91069
914 Sekondi-Takoradi GHA 103653
943 Palembang IDN 1222764
950 Padang IDN 534474
983 Palu IDN 142800
984 Pasuruan IDN 134019
991 Pangkal Pinang IDN 124000
1003 Pemalang IDN 103500
1004 Klaten IDN 103300
1007 Palangka Raya IDN 99693
1020 Padang Sidempuan IDN 91200
1045 Patna IND 917243
1114 Panihati IND 275990
1129 Patiala IND 238368
1142 Panipat IND 215218
1159 Parbhani IND 190255
1231 Pali IND 136842
1263 Pathankot IND 123930
1265 Palghat (Palakkad) IND 123289
1293 Pallavaram IND 111866
1319 Tellicherry (Thalassery) IND 103579
1339 Palayankottai IND 97662
1345 Patan IND 96109
1436 Marv Dasht IRN 103579
1468 Palermo ITA 683794
1478 Padova ITA 211391
1484 Parma ITA 168717
SELECT * FROM City
WHERE ((ID < 800) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 900 AND 1500) AND
(Name LIKE 'Pa%' OR (Population > 103000 AND Population < 104000)));
ID Name Country Population
1 Kabul AFG 1780000
2 Qandahar AFG 237500
3 Herat AFG 186800
4 Mazar-e-Sharif AFG 127800
7 Haag NLD 440900
16 Haarlem NLD 148772
25 Haarlemmermeer NLD 110722
33 Willemstad ANT 2345
34 Tirana ALB 270000
55 Andorra la Vella AND 21189
56 Luanda AGO 2022000
57 Huambo AGO 163100
58 Lobito AGO 130000
59 Benguela AGO 128300
60 Namibe AGO 118200
61 South Hill AIA 961
62 The Valley AIA 595
64 Dubai ARE 669181
65 Abu Dhabi ARE 398695
66 Sharja ARE 320095
67 al-Ayn ARE 225970
68 Ajman ARE 114395
129 Oranjestad ABW 29034
191 Hamilton BMU 1200
528 Hartlepool GBR 92000
529 Halifax GBR 91069
914 Sekondi-Takoradi GHA 103653
943 Palembang IDN 1222764
950 Padang IDN 534474
983 Palu IDN 142800
984 Pasuruan IDN 134019
991 Pangkal Pinang IDN 124000
1003 Pemalang IDN 103500
1004 Klaten IDN 103300
1007 Palangka Raya IDN 99693
1020 Padang Sidempuan IDN 91200
1045 Patna IND 917243
1114 Panihati IND 275990
1129 Patiala IND 238368
1142 Panipat IND 215218
1159 Parbhani IND 190255
1231 Pali IND 136842
1263 Pathankot IND 123930
1265 Palghat (Palakkad) IND 123289
1293 Pallavaram IND 111866
1319 Tellicherry (Thalassery) IND 103579
1339 Palayankottai IND 97662
1345 Patan IND 96109
1436 Marv Dasht IRN 103579
1468 Palermo ITA 683794
1478 Padova ITA 211391
1484 Parma ITA 168717
SELECT * FROM City USE INDEX ()
WHERE ((ID < 200) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 100 AND 200) AND
(Name LIKE 'Pa%' OR (Population > 103000 AND Population < 104000)));
ID Name Country Population
1 Kabul AFG 1780000
2 Qandahar AFG 237500
3 Herat AFG 186800
4 Mazar-e-Sharif AFG 127800
7 Haag NLD 440900
16 Haarlem NLD 148772
25 Haarlemmermeer NLD 110722
33 Willemstad ANT 2345
34 Tirana ALB 270000
55 Andorra la Vella AND 21189
56 Luanda AGO 2022000
57 Huambo AGO 163100
58 Lobito AGO 130000
59 Benguela AGO 128300
60 Namibe AGO 118200
61 South Hill AIA 961
62 The Valley AIA 595
64 Dubai ARE 669181
65 Abu Dhabi ARE 398695
66 Sharja ARE 320095
67 al-Ayn ARE 225970
68 Ajman ARE 114395
100 Paraná ARG 207041
129 Oranjestad ABW 29034
167 Jamalpur BGD 103556
168 Pabna BGD 103277
189 Parakou BEN 103577
191 Hamilton BMU 1200
SELECT * FROM City
WHERE ((ID < 200) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
OR ((ID BETWEEN 100 AND 200) AND
(Name LIKE 'Pa%' OR (Population > 103000 AND Population < 104000)));
ID Name Country Population
1 Kabul AFG 1780000
2 Qandahar AFG 237500
3 Herat AFG 186800
4 Mazar-e-Sharif AFG 127800
7 Haag NLD 440900
16 Haarlem NLD 148772
25 Haarlemmermeer NLD 110722
33 Willemstad ANT 2345
34 Tirana ALB 270000
55 Andorra la Vella AND 21189
56 Luanda AGO 2022000
57 Huambo AGO 163100
58 Lobito AGO 130000
59 Benguela AGO 128300
60 Namibe AGO 118200
61 South Hill AIA 961
62 The Valley AIA 595
64 Dubai ARE 669181
65 Abu Dhabi ARE 398695
66 Sharja ARE 320095
67 al-Ayn ARE 225970
68 Ajman ARE 114395
100 Paraná ARG 207041
129 Oranjestad ABW 29034
167 Jamalpur BGD 103556
168 Pabna BGD 103277
189 Parakou BEN 103577
191 Hamilton BMU 1200
EXPLAIN
SELECT * FROM City WHERE Population > 101000 AND Population < 102000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 39 Using index condition
EXPLAIN
SELECT * FROM City WHERE Population > 101000 AND Population < 110000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 328 Using index condition
EXPLAIN
SELECT * FROM City WHERE Country < 'C';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country Country 3 NULL 435 Using index condition
EXPLAIN
SELECT * FROM City WHERE Country < 'AGO';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country Country 3 NULL 5 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name BETWEEN 'P' AND 'S';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 221 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name BETWEEN 'P' AND 'Pb';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 39 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 3400 AND 3800;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 401 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 3790 AND 3800;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 11 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name LIKE 'P%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 135 Using index condition
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 102000) AND
(Country < 'C' OR Name BETWEEN 'P' AND 'S')) OR
((ID BETWEEN 3400 AND 3800) AND
(Country < 'AGO' OR Name LIKE 'Pa%'));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name Country,Name,Population 3,35,4 NULL 83 Using sort_union(Country,Name,Population); Using where
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 110000) AND
(Country < 'AGO' OR Name BETWEEN 'P' AND 'Pb')) OR
((ID BETWEEN 3790 AND 3800) AND
(Country < 'C' OR Name LIKE 'P%'));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name Country,Name,PRIMARY 3,35,4 NULL 55 Using sort_union(Country,Name,PRIMARY); Using where
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 102000) AND
(Country < 'C' OR Name BETWEEN 'P' AND 'S')) OR
((ID BETWEEN 3400 AND 3800) AND
(Country < 'AGO' OR Name LIKE 'Pa%'));
ID Name Country Population
169 Naogaon BGD 101266
205 Francistown BWA 101805
417 Itaituba BRA 101320
418 Araras BRA 101046
751 Potchefstroom ZAF 101817
2909 Puno PER 101578
3463 Pavlograd UKR 127000
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 102000) AND
(Country < 'C' OR Name BETWEEN 'P' AND 'S')) OR
((ID BETWEEN 3400 AND 3800) AND
(Country < 'AGO' OR Name LIKE 'Pa%'));
ID Name Country Population
169 Naogaon BGD 101266
205 Francistown BWA 101805
417 Itaituba BRA 101320
418 Araras BRA 101046
751 Potchefstroom ZAF 101817
2909 Puno PER 101578
3463 Pavlograd UKR 127000
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 110000) AND
(Country < 'AGO' OR Name BETWEEN 'P' AND 'Pb')) OR
((ID BETWEEN 3790 AND 3800) AND
(Country < 'C' OR Name LIKE 'P%'));
ID Name Country Population
168 Pabna BGD 103277
189 Parakou BEN 103577
750 Paarl ZAF 105768
2865 Pak Pattan PAK 107800
3797 Philadelphia USA 1517550
3798 Phoenix USA 1321045
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 110000) AND
(Country < 'AGO' OR Name BETWEEN 'P' AND 'Pb')) OR
((ID BETWEEN 3790 AND 3800) AND
(Country < 'C' OR Name LIKE 'P%'));
ID Name Country Population
168 Pabna BGD 103277
189 Parakou BEN 103577
750 Paarl ZAF 105768
2865 Pak Pattan PAK 107800
3797 Philadelphia USA 1517550
3798 Phoenix USA 1321045
CREATE INDEX CountryPopulation ON City(Country,Population);
EXPLAIN
SELECT * FROM City WHERE Name LIKE 'Pas%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 4 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name LIKE 'P%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 135 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Population > 101000 AND Population < 103000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 81 Using index condition
EXPLAIN
SELECT * FROM City WHERE Country='USA';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref Country,CountryPopulation Country 3 const 267 Using index condition
EXPLAIN
SELECT * FROM City WHERE Country='FIN';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref Country,CountryPopulation Country 3 const 7 Using index condition
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'Pas%')
AND Country='USA';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Population,Country,Name,CountryPopulation CountryPopulation,Name 7,35 NULL 14 Using sort_union(CountryPopulation,Name); Using where
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'P%')
AND Country='EST';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref Population,Country,Name,CountryPopulation Country 3 const 2 Using index condition; Using where
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'Pas%')
AND Country='USA';
ID Name Country Population
3943 Pasadena USA 141674
3953 Pasadena USA 133936
4023 Gary USA 102746
4024 Berkeley USA 102743
4025 Santa Clara USA 102361
4026 Green Bay USA 102313
4027 Cape Coral USA 102286
4028 Arvada USA 102153
4029 Pueblo USA 102121
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'Pas%')
AND Country='USA';
ID Name Country Population
3943 Pasadena USA 141674
3953 Pasadena USA 133936
4023 Gary USA 102746
4024 Berkeley USA 102743
4025 Santa Clara USA 102361
4026 Green Bay USA 102313
4027 Cape Coral USA 102286
4028 Arvada USA 102153
4029 Pueblo USA 102121
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'P%')
AND Country='FIN';
ID Name Country Population
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'P%')
AND Country='FIN';
ID Name Country Population
CREATE INDEX CountryName ON City(Country,Name);
EXPLAIN
SELECT * FROM City WHERE Country='USA';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref Country,CountryPopulation,CountryName Country 3 const 267 Using index condition
EXPLAIN
SELECT * FROM City WHERE Country='FIN';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref Country,CountryPopulation,CountryName CountryName 3 const 5 Using index condition
EXPLAIN
SELECT * FROM City WHERE Country='BRA';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref Country,CountryPopulation,CountryName CountryName 3 const 221 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 3790 AND 3800;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 11 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 4025 AND 4035;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 11 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 4028 AND 4032;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 5 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 3500 AND 3800;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 301 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 4000 AND 4300;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 80 Using index condition
EXPLAIN
SELECT * FROM City WHERE ID BETWEEN 250 and 260 ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY PRIMARY 4 NULL 11 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Population > 101000 AND Population < 102000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 39 Using index condition
EXPLAIN
SELECT * FROM City WHERE (Population > 101000 AND Population < 103000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population Population 4 NULL 81 Using index condition
EXPLAIN
SELECT * FROM City WHERE Name LIKE 'Pa%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Name Name 35 NULL 41 Using index condition
set @tmp_range_vs_index_merge=@@optimizer_switch;
set optimizer_switch='extended_keys=off';
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4025 AND 4035);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name,CountryPopulation,CountryName CountryPopulation,PRIMARY 7,4 NULL 14 Using sort_union(CountryPopulation,PRIMARY); Using where
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 103000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4028 AND 4032);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name,CountryPopulation,CountryName CountryName,PRIMARY 38,4 NULL 11 Using sort_union(CountryName,PRIMARY); Using where
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 110000) OR
ID BETWEEN 3500 AND 3800) AND Country='FIN'
AND (Name BETWEEN 'P' AND 'T' OR ID BETWEEN 4000 AND 4300);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ref PRIMARY,Population,Country,Name,CountryPopulation,CountryName CountryName 3 const 5 Using index condition; Using where
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4025 AND 4035);
ID Name Country Population
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4025 AND 4035);
ID Name Country Population
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4028 AND 4032);
ID Name Country Population
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4028 AND 4032);
ID Name Country Population
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='FIN'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4025 AND 4035);
ID Name Country Population
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='FIN'
AND (Name LIKE 'Pa%' OR ID BETWEEN 4025 AND 4035);
ID Name Country Population
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 and Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
OR (Name LIKE 'Pa%' OR ID BETWEEN 250 AND 260) AND Country='BRA';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge PRIMARY,Population,Country,Name,CountryPopulation,CountryName CountryPopulation,PRIMARY,CountryName 7,4,38 NULL 35 Using sort_union(CountryPopulation,PRIMARY,CountryName); Using where
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 and Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
OR (Name LIKE 'Pa%' OR ID BETWEEN 250 AND 260) AND Country='BRA';
ID Name Country Population
250 Mauá BRA 375055
251 Carapicuíba BRA 357552
252 Olinda BRA 354732
253 Campina Grande BRA 352497
254 São José do Rio Preto BRA 351944
255 Caxias do Sul BRA 349581
256 Moji das Cruzes BRA 339194
257 Diadema BRA 335078
258 Aparecida de Goiânia BRA 324662
259 Piracicaba BRA 319104
260 Cariacica BRA 319033
285 Paulista BRA 248473
339 Passo Fundo BRA 166343
364 Parnaíba BRA 129756
372 Paranaguá BRA 126076
379 Palmas BRA 121919
386 Patos de Minas BRA 119262
424 Passos BRA 98570
430 Paulo Afonso BRA 97291
435 Parnamirim BRA 96210
448 Patos BRA 90519
451 Palhoça BRA 89465
3793 New York USA 8008278
3794 Los Angeles USA 3694820
3795 Chicago USA 2896016
3796 Houston USA 1953631
3797 Philadelphia USA 1517550
3798 Phoenix USA 1321045
3799 San Diego USA 1223400
3800 Dallas USA 1188580
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City
WHERE ((Population > 101000 and Population < 102000) OR
ID BETWEEN 3790 AND 3800) AND Country='USA'
OR (Name LIKE 'Pa%' OR ID BETWEEN 250 AND 260) AND Country='BRA';
ID Name Country Population
250 Mauá BRA 375055
251 Carapicuíba BRA 357552
252 Olinda BRA 354732
253 Campina Grande BRA 352497
254 São José do Rio Preto BRA 351944
255 Caxias do Sul BRA 349581
256 Moji das Cruzes BRA 339194
257 Diadema BRA 335078
258 Aparecida de Goiânia BRA 324662
259 Piracicaba BRA 319104
260 Cariacica BRA 319033
285 Paulista BRA 248473
339 Passo Fundo BRA 166343
364 Parnaíba BRA 129756
372 Paranaguá BRA 126076
379 Palmas BRA 121919
386 Patos de Minas BRA 119262
424 Passos BRA 98570
430 Paulo Afonso BRA 97291
435 Parnamirim BRA 96210
448 Patos BRA 90519
451 Palhoça BRA 89465
3793 New York USA 8008278
3794 Los Angeles USA 3694820
3795 Chicago USA 2896016
3796 Houston USA 1953631
3797 Philadelphia USA 1517550
3798 Phoenix USA 1321045
3799 San Diego USA 1223400
3800 Dallas USA 1188580
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 11000) OR
ID BETWEEN 3500 AND 3800) AND Country='USA'
AND (Name LIKE 'P%' OR ID BETWEEN 4000 AND 4300);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY,Population,Country,Name,CountryPopulation,CountryName CountryName 38 NULL 23 Using index condition; Using where
EXPLAIN
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 11000) OR
ID BETWEEN 3500 AND 3800) AND Country='USA'
AND (Name LIKE 'Pho%' OR ID BETWEEN 4000 AND 4300);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range PRIMARY,Population,Country,Name,CountryPopulation,CountryName Name 35 NULL 1 Using where
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 11000) OR
ID BETWEEN 3500 AND 3800) AND Country='USA'
AND (Name LIKE 'P%' OR ID BETWEEN 4000 AND 4300);
ID Name Country Population
3797 Philadelphia USA 1517550
3798 Phoenix USA 1321045
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 11000) OR
ID BETWEEN 3500 AND 3800) AND Country='USA'
AND (Name LIKE 'P%' OR ID BETWEEN 4000 AND 4300);
ID Name Country Population
3797 Philadelphia USA 1517550
3798 Phoenix USA 1321045
SELECT * FROM City USE INDEX ()
WHERE ((Population > 101000 AND Population < 11000) OR
ID BETWEEN 3500 AND 3800) AND Country='USA'
AND (Name LIKE 'Pho%' OR ID BETWEEN 4000 AND 4300);
ID Name Country Population
3798 Phoenix USA 1321045
SELECT * FROM City
WHERE ((Population > 101000 AND Population < 11000) OR
ID BETWEEN 3500 AND 3800) AND Country='USA'
AND (Name LIKE 'Pho%' OR ID BETWEEN 4000 AND 4300);
ID Name Country Population
3798 Phoenix USA 1321045
DROP INDEX Population ON City;
DROP INDEX Name ON City;
set optimizer_switch=@tmp_range_vs_index_merge;
EXPLAIN
SELECT * FROM City
WHERE Country='USA' AND Population BETWEEN 101000 AND 102000 OR
Country='USA' AND Name LIKE 'Pa%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Country,CountryPopulation,CountryName CountryPopulation,CountryName 7,38 NULL 10 Using sort_union(CountryPopulation,CountryName); Using where
SELECT * FROM City USE INDEX()
WHERE Country='USA' AND Population BETWEEN 101000 AND 102000 OR
Country='USA' AND Name LIKE 'Pa%';
ID Name Country Population
3932 Paterson USA 149222
3943 Pasadena USA 141674
3953 Pasadena USA 133936
3967 Paradise USA 124682
3986 Palmdale USA 116670
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City
WHERE Country='USA' AND Population BETWEEN 101000 AND 102000 OR
Country='USA' AND Name LIKE 'Pa%';
ID Name Country Population
3932 Paterson USA 149222
3943 Pasadena USA 141674
3953 Pasadena USA 133936
3967 Paradise USA 124682
3986 Palmdale USA 116670
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
EXPLAIN
SELECT * FROM City
WHERE Country='USA' AND
(Population BETWEEN 101000 AND 102000 OR Name LIKE 'Pa%');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Country,CountryPopulation,CountryName CountryPopulation,CountryName 7,38 NULL 10 Using sort_union(CountryPopulation,CountryName); Using where
SELECT * FROM City
WHERE Country='USA' AND
(Population BETWEEN 101000 AND 102000 OR Name LIKE 'Pa%');
ID Name Country Population
3932 Paterson USA 149222
3943 Pasadena USA 141674
3953 Pasadena USA 133936
3967 Paradise USA 124682
3986 Palmdale USA 116670
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
SELECT * FROM City
WHERE Country='USA' AND
(Population BETWEEN 101000 AND 102000 OR Name LIKE 'Pa%');
ID Name Country Population
3932 Paterson USA 149222
3943 Pasadena USA 141674
3953 Pasadena USA 133936
3967 Paradise USA 124682
3986 Palmdale USA 116670
4030 Sandy USA 101853
4031 Athens-Clarke County USA 101489
4032 Cambridge USA 101355
set @save_optimizer_switch=@@optimizer_switch;
CREATE INDEX CityName on City(Name);
EXPLAIN SELECT Name, Country, Population FROM City WHERE
(Name='Manila' AND Country='PHL') OR
(Name='Addis Abeba' AND Country='ETH') OR
(Name='Jakarta' AND Country='IDN') OR
(Name='Bangalore' AND Country='IND') OR
(Name='Teheran' AND Country='IRN') OR
(Name='Roma' AND Country='ITA') OR
(Name='Delhi' AND Country='IND') OR
(Name='Venezia' AND Country='ITA') OR
(Name='Tokyo' AND Country='JPN') OR
(Name='Toronto' AND Country='CAN') OR
(Name='Peking' AND Country='CHN') OR
(Name='Lagos' AND Country='NGA') OR
(Name='Tijuana' AND Country='MEX') OR
(Name='Rabat' AND Country='MAR') OR
(Name='Seoul' AND Country='KOR') OR
(Name='Vancouver' AND Country='CAN') OR
(Name='Kaunas' AND Country='LTU') OR
(Name='Paris' AND Country='FRA') OR
(Name='Dakar' AND Country='SEN') OR
(Name='Basel' AND Country='CHE') OR
(Name='Praha' AND Country='CZE') OR
(Name='Ankara' AND Country='TUR') OR
(Name='Dresden' AND Country='DEU') OR
(Name='Lugansk' AND Country='UKR') OR
(Name='Caracas' AND Country='VEN') OR
(Name='Samara' AND Country='RUS') OR
(Name='Seattle' AND Country='USA');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Country,CountryPopulation,CountryName,CityName CountryName,CityName 38,35 NULL 28 Using sort_union(CountryName,CityName); Using where
SELECT Name, Country, Population FROM City WHERE
(Name='Manila' AND Country='PHL') OR
(Name='Addis Abeba' AND Country='ETH') OR
(Name='Jakarta' AND Country='IDN') OR
(Name='Bangalore' AND Country='IND') OR
(Name='Teheran' AND Country='IRN') OR
(Name='Roma' AND Country='ITA') OR
(Name='Delhi' AND Country='IND') OR
(Name='Venezia' AND Country='ITA') OR
(Name='Tokyo' AND Country='JPN') OR
(Name='Toronto' AND Country='CAN') OR
(Name='Peking' AND Country='CHN') OR
(Name='Lagos' AND Country='NGA') OR
(Name='Tijuana' AND Country='MEX') OR
(Name='Rabat' AND Country='MAR') OR
(Name='Seoul' AND Country='KOR') OR
(Name='Vancouver' AND Country='CAN') OR
(Name='Kaunas' AND Country='LTU') OR
(Name='Paris' AND Country='FRA') OR
(Name='Dakar' AND Country='SEN') OR
(Name='Basel' AND Country='CHE') OR
(Name='Praha' AND Country='CZE') OR
(Name='Ankara' AND Country='TUR') OR
(Name='Dresden' AND Country='DEU') OR
(Name='Lugansk' AND Country='UKR') OR
(Name='Caracas' AND Country='VEN') OR
(Name='Samara' AND Country='RUS') OR
(Name='Seattle' AND Country='USA');
Name Country Population
Addis Abeba ETH 2495000
Ankara TUR 3038159
Bangalore IND 2660088
Basel CHE 166700
Caracas VEN 1975294
Dakar SEN 785071
Delhi IND 7206704
Dresden DEU 476668
Jakarta IDN 9604900
Kaunas LTU 412639
Lagos NGA 1518000
Lugansk UKR 469000
Manila PHL 1581082
Paris FRA 2125246
Peking CHN 7472000
Praha CZE 1181126
Rabat MAR 623457
Roma ITA 2643581
Samara RUS 1156100
Seattle USA 563374
Seoul KOR 9981619
Teheran IRN 6758845
Tijuana MEX 1212232
Tokyo JPN 7980230
Toronto CAN 688275
Vancouver CAN 514008
Venezia ITA 277305
set optimizer_switch='index_merge=off';
EXPLAIN SELECT Name, Country, Population FROM City WHERE
(Name='Manila' AND Country='PHL') OR
(Name='Addis Abeba' AND Country='ETH') OR
(Name='Jakarta' AND Country='IDN') OR
(Name='Bangalore' AND Country='IND') OR
(Name='Teheran' AND Country='IRN') OR
(Name='Roma' AND Country='ITA') OR
(Name='Delhi' AND Country='IND') OR
(Name='Venezia' AND Country='ITA') OR
(Name='Tokyo' AND Country='JPN') OR
(Name='Toronto' AND Country='CAN') OR
(Name='Peking' AND Country='CHN') OR
(Name='Lagos' AND Country='NGA') OR
(Name='Tijuana' AND Country='MEX') OR
(Name='Rabat' AND Country='MAR') OR
(Name='Seoul' AND Country='KOR') OR
(Name='Vancouver' AND Country='CAN') OR
(Name='Kaunas' AND Country='LTU') OR
(Name='Paris' AND Country='FRA') OR
(Name='Dakar' AND Country='SEN') OR
(Name='Basel' AND Country='CHE') OR
(Name='Praha' AND Country='CZE') OR
(Name='Ankara' AND Country='TUR') OR
(Name='Dresden' AND Country='DEU') OR
(Name='Lugansk' AND Country='UKR') OR
(Name='Caracas' AND Country='VEN') OR
(Name='Samara' AND Country='RUS') OR
(Name='Seattle' AND Country='USA');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country,CountryPopulation,CountryName,CityName CountryName 38 NULL 28 Using index condition
SELECT Name, Country, Population FROM City WHERE
(Name='Manila' AND Country='PHL') OR
(Name='Addis Abeba' AND Country='ETH') OR
(Name='Jakarta' AND Country='IDN') OR
(Name='Bangalore' AND Country='IND') OR
(Name='Teheran' AND Country='IRN') OR
(Name='Roma' AND Country='ITA') OR
(Name='Delhi' AND Country='IND') OR
(Name='Venezia' AND Country='ITA') OR
(Name='Tokyo' AND Country='JPN') OR
(Name='Toronto' AND Country='CAN') OR
(Name='Peking' AND Country='CHN') OR
(Name='Lagos' AND Country='NGA') OR
(Name='Tijuana' AND Country='MEX') OR
(Name='Rabat' AND Country='MAR') OR
(Name='Seoul' AND Country='KOR') OR
(Name='Vancouver' AND Country='CAN') OR
(Name='Kaunas' AND Country='LTU') OR
(Name='Paris' AND Country='FRA') OR
(Name='Dakar' AND Country='SEN') OR
(Name='Basel' AND Country='CHE') OR
(Name='Praha' AND Country='CZE') OR
(Name='Ankara' AND Country='TUR') OR
(Name='Dresden' AND Country='DEU') OR
(Name='Lugansk' AND Country='UKR') OR
(Name='Caracas' AND Country='VEN') OR
(Name='Samara' AND Country='RUS') OR
(Name='Seattle' AND Country='USA');
Name Country Population
Addis Abeba ETH 2495000
Ankara TUR 3038159
Bangalore IND 2660088
Basel CHE 166700
Caracas VEN 1975294
Dakar SEN 785071
Delhi IND 7206704
Dresden DEU 476668
Jakarta IDN 9604900
Kaunas LTU 412639
Lagos NGA 1518000
Lugansk UKR 469000
Manila PHL 1581082
Paris FRA 2125246
Peking CHN 7472000
Praha CZE 1181126
Rabat MAR 623457
Roma ITA 2643581
Samara RUS 1156100
Seattle USA 563374
Seoul KOR 9981619
Teheran IRN 6758845
Tijuana MEX 1212232
Tokyo JPN 7980230
Toronto CAN 688275
Vancouver CAN 514008
Venezia ITA 277305
set optimizer_switch=@save_optimizer_switch;
#
# Bug mdev-585: range vs index-merge with ORDER BY ... LIMIT n
# (LP bug #637962)
#
DROP INDEX CountryPopulation ON City;
DROP INDEX CountryName ON City;
DROP INDEX CityName on City;
CREATE INDEX Name ON City(Name);
CREATE INDEX Population ON City(Population);
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City index_merge Country,Name,Population Name,Country 35,3 NULL # Using sort_union(Name,Country); Using where
FLUSH STATUS;
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000);
ID Name Country Population
384 Cabo Frio BRA 119503
387 Camaragibe BRA 118968
403 Catanduva BRA 107761
412 Cachoeirinha BRA 103240
508 Watford GBR 113080
509 Ipswich GBR 114000
510 Slough GBR 112000
511 Exeter GBR 111000
512 Cheltenham GBR 106000
513 Gloucester GBR 107000
514 Saint Helens GBR 106293
515 Sutton Coldfield GBR 106001
516 York GBR 104425
517 Oldham GBR 103931
518 Basildon GBR 100924
519 Worthing GBR 100000
635 Mallawi EGY 119283
636 Bilbays EGY 113608
637 Mit Ghamr EGY 101801
638 al-Arish EGY 100447
701 Tarragona ESP 113016
702 Lleida (Lérida) ESP 112207
703 Jaén ESP 109247
704 Ourense (Orense) ESP 109120
705 Mataró ESP 104095
706 Algeciras ESP 103106
707 Marbella ESP 101144
759 Gonder ETH 112249
869 Cabuyao PHL 106630
870 Calapan PHL 105910
873 Cauayan PHL 103952
903 Serekunda GMB 102600
909 Sohumi GEO 111700
913 Tema GHA 109975
914 Sekondi-Takoradi GHA 103653
924 Villa Nueva GTM 101295
1844 Cape Breton CAN 114733
1847 Cambridge CAN 109186
2406 Herakleion GRC 116178
2407 Kallithea GRC 114233
2408 Larisa GRC 113090
2908 Cajamarca PER 108009
3002 Besançon FRA 117733
3003 Caen FRA 113987
3004 Orléans FRA 113126
3005 Mulhouse FRA 110359
3006 Rouen FRA 106592
3007 Boulogne-Billancourt FRA 106367
3008 Perpignan FRA 105115
3009 Nancy FRA 103605
3411 Ceyhan TUR 102412
3567 Carúpano VEN 119639
3568 Catia La Mar VEN 117012
3571 Calabozo VEN 107146
3786 Cam Ranh VNM 114041
3792 Tartu EST 101246
4002 Carrollton USA 109576
4027 Cape Coral USA 102286
4032 Cambridge USA 101355
SHOW STATUS LIKE 'Handler_read_%';
Variable_name Value
Handler_read_first 0
Handler_read_key 2
Handler_read_last 0
Handler_read_next 385
Handler_read_prev 0
Handler_read_retry 0
Handler_read_rnd 377
Handler_read_rnd_deleted 0
Handler_read_rnd_next 0
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000)
ORDER BY Population LIMIT 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country,Name,Population Population 4 NULL # Using where
FLUSH STATUS;
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000)
ORDER BY Population LIMIT 5;
ID Name Country Population
519 Worthing GBR 100000
638 al-Arish EGY 100447
518 Basildon GBR 100924
707 Marbella ESP 101144
3792 Tartu EST 101246
SHOW STATUS LIKE 'Handler_read_%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 59
Handler_read_prev 0
Handler_read_retry 0
Handler_read_rnd 0
Handler_read_rnd_deleted 0
Handler_read_rnd_next 0
set @tmp_mdev585=@@optimizer_use_condition_selectivity;
set optimizer_use_condition_selectivity=1;
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000)
ORDER BY Population LIMIT 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country,Name,Population Population 4 NULL # Using where
FLUSH STATUS;
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000)
ORDER BY Population LIMIT 5;
ID Name Country Population
519 Worthing GBR 100000
638 al-Arish EGY 100447
518 Basildon GBR 100924
707 Marbella ESP 101144
3792 Tartu EST 101246
SHOW STATUS LIKE 'Handler_read_%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 59
Handler_read_prev 0
Handler_read_retry 0
Handler_read_rnd 0
Handler_read_rnd_deleted 0
Handler_read_rnd_next 0
set optimizer_use_condition_selectivity=@tmp_mdev585;
set optimizer_switch='index_merge=off';
EXPLAIN
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000)
ORDER BY Population LIMIT 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Country,Name,Population Population 4 NULL # Using index condition; Using where
FLUSH STATUS;
SELECT * FROM City
WHERE ((Name > 'Ca' AND Name < 'Cf') OR (Country > 'E' AND Country < 'H'))
AND (Population >= 100000 AND Population < 120000)
ORDER BY Population LIMIT 5;
ID Name Country Population
519 Worthing GBR 100000
638 al-Arish EGY 100447
518 Basildon GBR 100924
707 Marbella ESP 101144
3792 Tartu EST 101246
SHOW STATUS LIKE 'Handler_read_%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 59
Handler_read_prev 0
Handler_read_retry 0
Handler_read_rnd 0
Handler_read_rnd_deleted 0
Handler_read_rnd_next 0
set optimizer_switch=@save_optimizer_switch;
DROP DATABASE world;
use test;
CREATE TABLE t1 (
id int(10) unsigned NOT NULL auto_increment,
account_id int(10) unsigned NOT NULL,
first_name varchar(50) default NULL,
middle_name varchar(50) default NULL,
last_name varchar(100) default NULL,
home_address_1 varchar(150) default NULL,
home_city varchar(75) default NULL,
home_state char(2) default NULL,
home_postal_code varchar(50) default NULL,
home_county varchar(75) default NULL,
home_country char(3) default NULL,
work_address_1 varchar(150) default NULL,
work_city varchar(75) default NULL,
work_state char(2) default NULL,
work_postal_code varchar(50) default NULL,
work_county varchar(75) default NULL,
work_country char(3) default NULL,
login varchar(50) NOT NULL,
PRIMARY KEY (id),
KEY login (login,account_id),
KEY account_id (account_id),
KEY user_home_country_indx (home_country),
KEY user_work_country_indx (work_country),
KEY user_home_state_indx (home_state),
KEY user_work_state_indx (work_state),
KEY user_home_city_indx (home_city),
KEY user_work_city_indx (work_city),
KEY user_first_name_indx (first_name),
KEY user_last_name_indx (last_name)
);
insert into t1(account_id, login, home_state, work_state) values
(1, 'pw', 'ia', 'ia'), (1, 'pw', 'ia', 'ia'), (1, 'pw', 'ia', 'ia'),
(1, 'pw', 'ia', 'ia'), (1, 'pw', 'ia', 'ia'), (1, 'pw', 'ia', 'ia');
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
insert into t1(account_id, login, home_state, work_state)
select 1, 'pw', 'ak', 'ak' from t1;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
select count(*) from t1 where account_id = 1;
count(*)
3072
select * from t1
where (home_state = 'ia' or work_state='ia') and account_id = 1;
id account_id first_name middle_name last_name home_address_1 home_city home_state home_postal_code home_county home_country work_address_1 work_city work_state work_postal_code work_county work_country login
1 1 NULL NULL NULL NULL NULL ia NULL NULL NULL NULL NULL ia NULL NULL NULL pw
2 1 NULL NULL NULL NULL NULL ia NULL NULL NULL NULL NULL ia NULL NULL NULL pw
3 1 NULL NULL NULL NULL NULL ia NULL NULL NULL NULL NULL ia NULL NULL NULL pw
4 1 NULL NULL NULL NULL NULL ia NULL NULL NULL NULL NULL ia NULL NULL NULL pw
5 1 NULL NULL NULL NULL NULL ia NULL NULL NULL NULL NULL ia NULL NULL NULL pw
6 1 NULL NULL NULL NULL NULL ia NULL NULL NULL NULL NULL ia NULL NULL NULL pw
explain
select * from t1
where (home_state = 'ia' or work_state='ia') and account_id = 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge account_id,user_home_state_indx,user_work_state_indx user_home_state_indx,user_work_state_indx 3,3 NULL 6 Using union(user_home_state_indx,user_work_state_indx); Using where
drop table t1;
CREATE TABLE t1 (
c1 int(11) NOT NULL auto_increment,
c2 decimal(10,0) default NULL,
c3 decimal(10,0) default NULL,
c4 decimal(10,0) default NULL,
c5 decimal(10,0) default NULL,
cp decimal(1,0) default NULL,
ce decimal(10,0) default NULL,
cdata char(20),
PRIMARY KEY (c1),
KEY k1 (c2,c3,cp,ce),
KEY k2 (c4,c5,cp,ce)
);
insert into t1 (c2, c3, c4, c5, cp) values(1,1,1,1,1);
insert into t1 (c2, c3, c4, c5, cp) values(2,1,1,1,4);
insert into t1 (c2, c3, c4, c5, cp) values(2,1,2,1,1);
insert into t1 (c2, c3, c4, c5, cp) values(2,1,3,1,4);
insert into t1 (c2, c3, c4, c5, cp) values(3,1,4,1,4);
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
insert into t1 (c2, c3, c4, c5, cp)
select c2, c3, c4, c5, cp from t1 where cp = 4;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
explain
select * from t1 where (c2=1 and c3=1) or (c4=2 and c5=1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge k1,k2 k1,k2 12,12 NULL 2 Using sort_union(k1,k2); Using where
explain
select * from t1
where (c2=1 and c3=1 and cp=1) or (c4=2 and c5=1 and cp=1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge k1,k2 k1,k2 14,14 NULL 2 Using sort_union(k1,k2); Using where
explain
select * from t1
where ((c2=1 and c3=1) or (c4=2 and c5=1)) and cp=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge k1,k2 k1,k2 14,14 NULL 2 Using sort_union(k1,k2); Using where
select * from t1
where (c2=1 and c3=1 and cp=1) or (c4=2 and c5=1 and cp=1);
c1 c2 c3 c4 c5 cp ce cdata
1 1 1 1 1 1 NULL NULL
3 2 1 2 1 1 NULL NULL
select * from t1
where ((c2=1 and c3=1) or (c4=2 and c5=1)) and cp=1;
c1 c2 c3 c4 c5 cp ce cdata
1 1 1 1 1 1 NULL NULL
3 2 1 2 1 1 NULL NULL
drop table t1;
create table t1 (
c1 int auto_increment primary key,
c2 char(20),
c3 char (20),
c4 int
);
alter table t1 add key k1 (c2);
alter table t1 add key k2 (c3);
alter table t1 add key k3 (c4);
insert into t1 values(null, 'a', 'b', 0);
insert into t1 values(null, 'c', 'b', 0);
insert into t1 values(null, 'a', 'd', 0);
insert into t1 values(null, 'ccc', 'qqq', 0);
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3) select c2,c3 from t1 where c2 != 'a';
insert into t1 (c2,c3,c4) select c2,c3,1 from t1 where c2 != 'a';
insert into t1 (c2,c3,c4) select c2,c3,2 from t1 where c2 != 'a';
insert into t1 (c2,c3,c4) select c2,c3,3 from t1 where c2 != 'a';
insert into t1 (c2,c3,c4) select c2,c3,4 from t1 where c2 != 'a';
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
select count(*) from t1 where (c2='e' OR c3='q');
count(*)
0
select count(*) from t1 where c4 != 0;
count(*)
3840
explain
select distinct c1 from t1 where (c2='e' OR c3='q');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge k1,k2 k1,k2 21,21 NULL 2 Using union(k1,k2); Using where
explain
select distinct c1 from t1 where (c4!= 0) AND (c2='e' OR c3='q');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge k1,k2,k3 k1,k2 21,21 NULL 2 Using union(k1,k2); Using where
drop table t1;
create table t1 (
id int unsigned auto_increment primary key,
c1 char(12),
c2 char(15),
c3 char(1)
);
insert into t1 (c3) values ('1'), ('2');
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
insert into t1 (c3) select c3 from t1;
update t1 set c1=lpad(id+1000, 12, ' '), c2=lpad(id+10000, 15, ' ');
alter table t1 add unique index (c1), add unique index (c2), add index (c3);
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
explain
select * from t1 where (c1=' 100000' or c2=' 2000000');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge c1,c2 c1,c2 13,16 NULL 2 Using union(c1,c2); Using where
explain
select * from t1 where (c1=' 100000' or c2=' 2000000') and c3='2';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge c1,c2,c3 c1,c2 13,16 NULL 2 Using union(c1,c2); Using where
select * from t1 where (c1=' 100000' or c2=' 2000000');
id c1 c2 c3
select * from t1 where (c1=' 100000' or c2=' 2000000') and c3='2';
id c1 c2 c3
drop table t1;
CREATE TABLE t1 (
a smallint DEFAULT NULL,
pk int NOT NULL AUTO_INCREMENT PRIMARY KEY,
b varchar(10) DEFAULT NULL,
c varchar(64) DEFAULT NULL,
INDEX idx1 (a),
INDEX idx2 (b),
INDEX idx3 (c)
);
SELECT COUNT(*) FROM t1 IGNORE INDEX (idx2,idx3)
WHERE c = 'i' OR b IN ( 'Arkansas' , 'd' , 'pdib' , 'can' ) OR
(pk BETWEEN 120 AND 79 + 255 OR a IN ( 4 , 179 , 1 ) ) AND a > 8 ;
COUNT(*)
5
SELECT COUNT(*) FROM t1
WHERE c = 'i' OR b IN ( 'Arkansas' , 'd' , 'pdib' , 'can' ) OR
(pk BETWEEN 120 AND 79 + 255 OR a IN ( 4 , 179 , 1 ) ) AND a > 8 ;
COUNT(*)
5
EXPLAIN
SELECT COUNT(*) FROM t1
WHERE c = 'i' OR b IN ( 'Arkansas' , 'd' , 'pdib' , 'can' ) OR
(pk BETWEEN 120 AND 79 + 255 OR a IN ( 4 , 179 , 1 ) ) AND a > 8 ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge PRIMARY,idx1,idx2,idx3 idx3,idx2,PRIMARY,idx1 67,13,4,3 NULL 9 Using sort_union(idx3,idx2,PRIMARY,idx1); Using where
DROP TABLE t1;
CREATE TABLE t1 (
f1 int, f2 int, f3 int, f4 int, f5 int,
PRIMARY KEY (f4), KEY (f1), KEY (f2), KEY (f3)
) ;
INSERT INTO t1 VALUES (0,0,NULL,9,5), (0,0,1,9425,NULL);
SELECT f5 FROM t1
WHERE f2 != 1 OR f1 IS NULL OR f4 = 4 OR
f2 AND (f4 BETWEEN 6 AND 255 OR f3 IS NULL);
f5
5
NULL
DROP TABLE t1;
CREATE TABLE t1 (
f1 int, f2 int, f3 int, f4 int,
PRIMARY KEY (f1), KEY (f3), KEY (f4)
);
INSERT INTO t1 VALUES (1,0,0,0), (2,0,0,0), (3,0,0,0);
INSERT INTO t1 VALUES (9,0,2,6), (9930,0,0,NULL);
insert into t1 select seq,seq,seq,seq from seq_100_to_400;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
SET SESSION optimizer_switch='index_merge_intersection=off';
SET SESSION optimizer_switch='index_merge_sort_union=off';
SET SESSION optimizer_switch='index_merge_union=off';
EXPLAIN
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL PRIMARY,f3,f4 NULL NULL NULL 306 Using where
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
f1 f2 f3 f4
9 0 2 6
SET SESSION optimizer_switch='index_merge_union=on';
EXPLAIN
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge PRIMARY,f3,f4 f3,PRIMARY,f3 5,4,5 NULL 3 Using union(f3,PRIMARY,f3); Using where
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
f1 f2 f3 f4
9 0 2 6
INSERT INTO t1 VALUES
(93,0,3,6), (9933,0,3,3), (94,0,4,6), (9934,0,4,4),
(95,0,5,6), (9935,0,5,5), (96,0,6,6), (9936,0,6,6),
(97,0,7,6), (9937,0,7,7), (98,0,8,6), (9938,0,8,8),
(99,0,9,6), (9939,0,9,9);
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
SET SESSION optimizer_switch='index_merge_union=off';
EXPLAIN
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL PRIMARY,f3,f4 NULL NULL NULL 320 Using where
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
f1 f2 f3 f4
9 0 2 6
SET SESSION optimizer_switch='index_merge_union=on';
EXPLAIN
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge PRIMARY,f3,f4 f3,PRIMARY,f3 5,4,5 NULL 3 Using union(f3,PRIMARY,f3); Using where
SELECT * FROM t1 FORCE KEY (PRIMARY,f3,f4)
WHERE ( f3 = 1 OR f1 = 7 ) AND f1 < 10
OR f3 BETWEEN 2 AND 2 AND ( f3 = 1 OR f4 < 7 );
f1 f2 f3 f4
9 0 2 6
SET SESSION optimizer_switch=DEFAULT;
DROP TABLE t1;
CREATE TABLE t1 (f1 int) ;
INSERT INTO t1 VALUES (0), (0);
CREATE TABLE t2 (f1 int, f2 int, f3 int, f4 int, INDEX idx (f3,f2)) ;
INSERT INTO t2 VALUES (5,6,0,0), (0,4,0,0);
CREATE TABLE t3 (f1 int, f2 int, INDEX idx1 (f2,f1) , INDEX idx2 (f1)) ;
INSERT INTO t3 VALUES (6,0),( 4,0);
SELECT * FROM t1,t2,t3
WHERE (t2.f3 = 1 OR t3.f1=t2.f1) AND t3.f1 <> t2.f2 AND t3.f2 = t2.f4;
f1 f1 f2 f3 f4 f1 f2
DROP TABLE t1,t2,t3;
CREATE TABLE t1 (
a int, b int, c int, d int,
PRIMARY KEY(b), INDEX idx1(d), INDEX idx2(d,b,c)
);
INSERT INTO t1 VALUES
(0,58,7,7),(0,63,2,0),(0,64,186,8),(0,65,1,-2), (0,71,190,-3),
(0,72,321,-7),(0,73,0,3),(0,74,5,25),(0,75,5,3);
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
SET SESSION optimizer_switch='index_merge_sort_union=off';
EXPLAIN
SELECT * FROM t1
WHERE t1.b>7 AND t1.d>1 AND t1.d<>8 OR t1.d>=7 AND t1.d<8 OR t1.d>7;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL PRIMARY,idx1,idx2 NULL NULL NULL 9 Using where
SELECT * FROM t1
WHERE t1.b>7 AND t1.d>1 AND t1.d<>8 OR t1.d>=7 AND t1.d<8 OR t1.d>7;
a b c d
0 58 7 7
0 64 186 8
0 73 0 3
0 74 5 25
0 75 5 3
SET SESSION optimizer_switch='index_merge_sort_union=on';
EXPLAIN
SELECT * FROM t1
WHERE t1.b>7 AND t1.d>1 AND t1.d<>8 OR t1.d>=7 AND t1.d<8 OR t1.d>7;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL PRIMARY,idx1,idx2 NULL NULL NULL 9 Using where
SELECT * FROM t1
WHERE t1.b>7 AND t1.d>1 AND t1.d<>8 OR t1.d>=7 AND t1.d<8 OR t1.d>7;
a b c d
0 58 7 7
0 64 186 8
0 73 0 3
0 74 5 25
0 75 5 3
SET SESSION optimizer_switch=DEFAULT;
DROP TABLE t1;
CREATE TABLE t1 (a int NOT NULL PRIMARY KEY, b int, c int, INDEX idx(c,b));
INSERT INTO t1 VALUES (19,1,NULL), (20,5,7);
EXPLAIN
SELECT * FROM t1
WHERE t1.a>300 AND t1.c!=0 AND t1.b>=350 AND t1.b<=400 AND
(t1.c=0 OR t1.a=500);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,idx PRIMARY 4 NULL 1 Using index condition; Using where
SELECT * FROM t1
WHERE t1.a>300 AND t1.c!=0 AND t1.b>=350 AND t1.b<=400 AND
(t1.c=0 OR t1.a=500);
a b c
DROP TABLE t1;
CREATE TABLE t1 (a int PRIMARY KEY, b int, INDEX idx(b));
INSERT INTO t1 VALUES (167,9999), (168,10000);
EXPLAIN
SELECT * FROM t1
WHERE a BETWEEN 4 AND 5 AND b IN (255,4) OR a IN (2,14,25) OR (a<2 or a>2);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,idx PRIMARY 0 NULL 2 Using index condition; Using where
SELECT * FROM t1
WHERE a BETWEEN 4 AND 5 AND b IN (255,4) OR a IN (2,14,25) OR (a<2 or a>2);
a b
167 9999
168 10000
DROP TABLE t1;
#
# MDEV-8603: Wrong result OR/AND condition over index fields
#
CREATE TABLE t1 (
id INT NOT NULL,
state VARCHAR(64),
capital VARCHAR(64),
UNIQUE KEY (id),
KEY state (state,id),
KEY capital (capital, id)
);
INSERT INTO t1 VALUES
(1,'Arizona','Phoenix'),
(2,'Hawaii','Honolulu'),
(3,'Georgia','Atlanta'),
(4,'Florida','Tallahassee'),
(5,'Alaska','Juneau'),
(6,'Michigan','Lansing'),
(7,'Pennsylvania','Harrisburg'),
(8,'Virginia','Richmond')
;
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
EXPLAIN
SELECT * FROM t1 FORCE KEY (state,capital)
WHERE ( state = 'Alabama' OR state >= 'Colorado' ) AND (id<9 or id>9)
OR ( capital >= 'Topeka' OR state = 'Kansas' ) AND state != 'Texas';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range state,capital state 71 NULL 8 Using index condition; Using where
SELECT * FROM t1 FORCE KEY (state,capital)
WHERE ( state = 'Alabama' OR state >= 'Colorado' ) AND (id<9 or id>9)
OR ( capital >= 'Topeka' OR state = 'Kansas' ) AND state != 'Texas';
id state capital
4 Florida Tallahassee
3 Georgia Atlanta
2 Hawaii Honolulu
6 Michigan Lansing
7 Pennsylvania Harrisburg
8 Virginia Richmond
DROP TABLE t1;
#
# mdev-11574: do not build index merge of two indexes when
# one index is an infix of the other index
#
set names utf8;
CREATE DATABASE world;
use world;
CREATE TABLE Country (
Code char(3) NOT NULL default '',
Name char(52) NOT NULL default '',
SurfaceArea float(10,2) NOT NULL default '0.00',
Population int(11) NOT NULL default '0',
Capital int(11) default NULL,
PRIMARY KEY (Code),
UNIQUE INDEX (Name)
);
CREATE TABLE City (
ID int(11) NOT NULL auto_increment,
Name char(35) NOT NULL default '',
Country char(3) NOT NULL default '',
Population int(11) NOT NULL default '0',
PRIMARY KEY (ID),
INDEX (Population),
INDEX (Country)
);
CREATE TABLE CountryLanguage (
Country char(3) NOT NULL default '',
Language char(30) NOT NULL default '',
Percentage float(3,1) NOT NULL default '0.0',
PRIMARY KEY (Country, Language),
INDEX (Percentage)
);
DROP INDEX Country ON City;
CREATE INDEX CountryName ON City(Country,Name);
CREATE INDEX Name ON City(Name);
select * from City
where
Country='FIN' AND Name IN ('Lahti','Imatra') OR
Country='RUS' AND Name IN ('St Petersburg', 'Moscow') OR
Country='SWE' AND Name IN ('Stockholm', 'Uppsala') OR
Country='DEU' AND Name IN ('Berlin', 'Bonn') OR
Country='BEL' AND Name IN ('Antwerpen', 'Gent') OR
Country='PRT' AND Name IN ('Braga', 'Porto') OR
Country='FRA' AND Name IN ('Paris', 'Marcel') OR
Country='POL' AND Name IN ('Warszawa', 'Wroclaw') OR
Country='NOR' AND Name IN ('Oslo', 'Bergen') OR
Country='ITA' AND Name IN ('Napoli', 'Venezia');
ID Name Country Population
175 Antwerpen BEL 446525
176 Gent BEL 224180
3068 Berlin DEU 3386667
3087 Bonn DEU 301048
3242 Lahti FIN 96921
2974 Paris FRA 2125246
1466 Napoli ITA 1002619
1474 Venezia ITA 277305
2808 Bergen NOR 230948
2807 Oslo NOR 508726
2928 Warszawa POL 1615369
2931 Wroclaw POL 636765
2918 Braga PRT 90535
2915 Porto PRT 273060
3580 Moscow RUS 8389200
3581 St Petersburg RUS 4694000
3048 Stockholm SWE 750348
3051 Uppsala SWE 189569
explain select * from City
where
Country='FIN' AND Name IN ('Lahti','Imatra') OR
Country='RUS' AND Name IN ('St Petersburg', 'Moscow') OR
Country='SWE' AND Name IN ('Stockholm', 'Uppsala') OR
Country='DEU' AND Name IN ('Berlin', 'Bonn') OR
Country='BEL' AND Name IN ('Antwerpen', 'Gent') OR
Country='PRT' AND Name IN ('Braga', 'Porto') OR
Country='FRA' AND Name IN ('Paris', 'Marcel') OR
Country='POL' AND Name IN ('Warszawa', 'Wroclaw') OR
Country='NOR' AND Name IN ('Oslo', 'Bergen') OR
Country='ITA' AND Name IN ('Napoli', 'Venezia');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range CountryName,Name CountryName 38 NULL 20 Using index condition
DROP DATABASE world;
set session optimizer_switch='index_merge_sort_intersection=default';
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