Simple Operating Systems （简称SOS）是一个可以运行在X86平台上（包括QEMU，BOCHS，VirtualBOX等模拟器上）的面向教学的微型嵌入式操作系统系列软件。从SOS-1到SOS9，逐步完成了一个从无（只有显示）到有（虚存、文件系统、线程、进程）的操作系统创建过程。通过分析、运行和修改此操作系统，会对操作系统的实际实现有更深入的的了解。这是第二部分 SOS-2。
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001206s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.079801s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001940s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001268s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003114s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000975s ]
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SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001036s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 397807 [ RunTime:0.030911s ]
