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 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 where
EXPLAIN
SELECT * FROM City
WHERE Population > 100000 AND Name LIKE 'Aba%' OR
Country IN ('CAN', 'ARG') AND ID < 3800 OR
Country < 'U' AND Name LIKE 'Zhu%' OR
ID BETWEEN 3800 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,Country,PRIMARY	35,3,4	NULL	132	Using sort_union(Name,Country,PRIMARY); 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 where
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 where
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 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 where
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	208	Using where
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 where
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 where
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 where
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 where
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 where
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 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	21	Using where
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	201	Using where
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	19	Using where
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	222	Using where
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 where
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	21	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 < 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	128	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 > 103000 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	128	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 where
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 where
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	436	Using where
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	6	Using where
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 where
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 where
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 where
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 where
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 where
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	84	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	56	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	5	Using where
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 where
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 where
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 where
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	6	Using where
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	15	Using sort_union(CountryPopulation,Name); Using where
EXPLAIN
SELECT * FROM City 
WHERE ((Population > 101000 AND Population < 103000) OR Name LIKE 'P%')
AND Country='FIN';
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	City	ref	Population,Country,Name,CountryPopulation	Country	3	const	6	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 where
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 where
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 where
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 where
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 where
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 where
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 where
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 where
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 where
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 where
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 where
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 where
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 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 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;
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
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	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	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	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	OK
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	8	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 (9,0,2,6), (9930,0,0,NULL);
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 != 1 );
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	PRIMARY,f3,f4	NULL	NULL	NULL	2	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 != 1 );
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 != 1 );
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	PRIMARY,f3,f4	NULL	NULL	NULL	2	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 != 1 );
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);
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 != 1 );
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	PRIMARY,f3,f4	NULL	NULL	NULL	16	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 != 1 );
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 != 1 );
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 != 1 );
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);
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 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;
set session optimizer_switch='index_merge_sort_intersection=default';