We’re working with web site preparing for massive growth. To make sure it handles large data sets as part of the process we work on generation test database of significant size as testing your application on table with 1000 rows may well give you very dangerous false sense of security. One of the process web [...]
Handling big result sets
Sometime it is needed to handle a lot of rows on client side. Usual way is send query via mysql_query and than handle the result in loop mysql_fetch_array (here I use PHP functions but they are common or similar for all APIs, including C). Consider table:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 | CREATE TABLE `longf` ( `f1` int(11) NOT NULL auto_increment, `f2` date default NULL, `f3` date default NULL, `f4` varchar(14) default NULL, `f5` varchar(6) default NULL, `f6` date default NULL, `f7` smallint(6) default NULL, `f8` smallint(6) default NULL, `f9` varchar(13) default NULL, `f10` varchar(39) default NULL, `f11` int(11) default NULL, `f12` float default NULL, `f13` int(11) default NULL, `f14` smallint(6) default NULL, `f15` varchar(39) default NULL, `f16` date default NULL, `f17` smallint(6) default NULL, `f18` int(11) NOT NULL, `f19` date default NULL, `f20` date default NULL, `f21` varchar(14) default NULL, `f22` varchar(6) default NULL, `f23` date default NULL, `f24` smallint(6) default NULL, `f25` smallint(6) default NULL, `f26` varchar(13) default NULL, `f27` varchar(39) default NULL, `f28` int(11) default NULL, `f29` float default NULL, `f30` int(11) default NULL, `f31` smallint(6) default NULL, `f32` varchar(39) default NULL, `f33` date default NULL, `f34` smallint(6) default NULL, `f35` int(11) NOT NULL, PRIMARY KEY (`f1`) ); select count(*) from longf; +----------+ | count(*) | +----------+ | 5242880 | +----------+ |

