SELECT Operating_system ,  count(*) FROM web_client_accelerator GROUP BY Operating_system
Find the number of web accelerators used for each Operating system.
PRAGMA foreign_keys=OFF;
BEGIN TRANSACTION;
CREATE TABLE IF NOT EXISTS "Web_client_accelerator" (
"id" int,
"name" text,
"Operating_system" text,
"Client" text,
"Connection" text,
primary key("id")
);
INSERT INTO Web_client_accelerator VALUES(1,'CACHEbox','Appliance (Linux)','End user, ISP','Broadband, Satellite, Wireless, Fiber, DSL');
INSERT INTO Web_client_accelerator VALUES(2,'CProxy','Windows','user','up to 756kbit/s');
INSERT INTO Web_client_accelerator VALUES(3,'Fasterfox','Windows, Mac, Linux and Mobile devices','user','Dialup, Wireless, Broadband, DSL');
INSERT INTO Web_client_accelerator VALUES(4,'fasTun','Any','All','Any');
INSERT INTO Web_client_accelerator VALUES(5,'Freewire','Windows, except NT and 95','ISP','Dial-up');
INSERT INTO Web_client_accelerator VALUES(6,'Google Web Accelerator (discontinued)','Windows','user/Google server','Broadband');
INSERT INTO Web_client_accelerator VALUES(7,'Heigh Speed','Windows','All','Any');
INSERT INTO Web_client_accelerator VALUES(8,'Netfury','Windows, Mac','End User, ISP','Dial-up, Broadband, DSL, ISDN, Satellite, Wireless');
INSERT INTO Web_client_accelerator VALUES(9,'Nitro','Windows, Mac','End User, ISP','Dial-up, Broadband, DSL, ISDN, Satellite, Wireless');
INSERT INTO Web_client_accelerator VALUES(10,'ONSPEED','Windows, Mac and Mobile devices','user','Dialup, Wireless, Broadband, DSL');
INSERT INTO Web_client_accelerator VALUES(11,'Opera Turbo','Android, Linux, Mac and Windows devices','user/Opera server','Any');
INSERT INTO Web_client_accelerator VALUES(12,'Polipo','Unix (Linux, *BSD, Mac OS X, others), Windows','user/ISP','Any');
INSERT INTO Web_client_accelerator VALUES(13,'Propel','Windows, Mac','End User, ISP','Dial, DSL, ISDN, Satellite, wireless');
INSERT INTO Web_client_accelerator VALUES(14,'Proxyconn Web Accelerator','Windows, Mac, Mobile devices','user','Dialup, Wireless, Broadband, DSL');
INSERT INTO Web_client_accelerator VALUES(15,'RabbIT','Any system with Java 1.6 VM available','ISP','Any');
INSERT INTO Web_client_accelerator VALUES(16,'Squid','Unix (Linux, *BSD, Mac OS X, others), Windows','user/ISP','Any');
INSERT INTO Web_client_accelerator VALUES(17,'Toonel','Windows, Linux, Mac OS, Symbian, WindowsMobile','user/ISP','Any');
INSERT INTO Web_client_accelerator VALUES(18,'WinGate','Windows (2000 onwards)','All','Any');
INSERT INTO Web_client_accelerator VALUES(19,'Ziproxy','Unix (Linux, *BSD, Mac OS X, others)','ISP','Any');
CREATE TABLE IF NOT EXISTS "browser" (
"id" int,
"name" text,
"market_share" real,
primary key("id")
);
INSERT INTO browser VALUES(1,'Internet Explorer',28.960000000000000852);
INSERT INTO browser VALUES(2,'Firefox',18.109999999999999431);
INSERT INTO browser VALUES(3,'Safari',8.5399999999999991473);
INSERT INTO browser VALUES(4,'Opera',1.1999999999999999555);
CREATE TABLE IF NOT EXISTS "accelerator_compatible_browser" (
"accelerator_id" int,
"browser_id" int,
"compatible_since_year" int,
primary key("accelerator_id", "browser_id"),
foreign key ("accelerator_id") references `Web_client_accelerator`("id"),
foreign key ("browser_id") references `browser`("id")
);
INSERT INTO accelerator_compatible_browser VALUES(1,1,1995);
INSERT INTO accelerator_compatible_browser VALUES(1,2,1996);
INSERT INTO accelerator_compatible_browser VALUES(2,3,1996);
INSERT INTO accelerator_compatible_browser VALUES(2,4,2000);
INSERT INTO accelerator_compatible_browser VALUES(3,1,2005);
INSERT INTO accelerator_compatible_browser VALUES(3,2,2007);
INSERT INTO accelerator_compatible_browser VALUES(3,3,2008);
INSERT INTO accelerator_compatible_browser VALUES(4,4,2009);
INSERT INTO accelerator_compatible_browser VALUES(9,1,2010);
COMMIT;


('Android, Linux, Mac and Windows devices', 1)
('Any', 1)
('Any system with Java 1.6 VM available', 1)
('Appliance (Linux)', 1)
('Unix (Linux, *BSD, Mac OS X, others)', 1)
('Unix (Linux, *BSD, Mac OS X, others), Windows', 2)
('Windows', 3)
('Windows (2000 onwards)', 1)
('Windows, Linux, Mac OS, Symbian, WindowsMobile', 1)
('Windows, Mac', 3)
('Windows, Mac and Mobile devices', 1)
('Windows, Mac, Linux and Mobile devices', 1)
('Windows, Mac, Mobile devices', 1)
('Windows, except NT and 95', 1)
