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DB2SQL性能调优秘笈

作者：托尼.安德鲁斯

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mobi/epub/pdf/awz3

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本书是一本不可多得的db2数据库性能调优秘笈，由拥有20余年db2工作经验的资深数据库专家撰写，amazon全五星评价畅销书。本书不仅详尽阐述了100余条sql语句优化的技巧和最佳实践、编写高性能sql语句的标准和原则，以及db2数据库性能优化的“15步法”，而且还包含大量案例，为解决各种复杂的db2性能问题提供了解决方案。

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CONNECT:[ UseTime:0.001681s ] mysql:host=127.0.0.1;port=3306;dbname=mqshop;charset=utf8
SHOW FULL COLUMNS FROM `ls_goods_category` [ RunTime:0.001181s ]
SELECT `id`,`name`,`pid`,`image`,`level`,`is_show`,`is_recommend` FROM `ls_goods_category` WHERE `is_show` = 1 AND `del` = 0 AND `level` = 1 ORDER BY `id` ASC,`sort` DESC [ RunTime:0.002120s ]
SELECT `id`,`name`,`pid`,`image`,`level`,`is_show`,`is_recommend` FROM `ls_goods_category` WHERE `is_show` = 1 AND `del` = 0 AND `level` = 2 ORDER BY `id` ASC,`sort` DESC [ RunTime:0.000644s ]
SELECT `id`,`name`,`pid`,`image`,`level`,`is_show`,`is_recommend` FROM `ls_goods_category` WHERE `is_show` = 1 AND `del` = 0 AND `level` = 3 ORDER BY `sort` DESC [ RunTime:0.000376s ]
SHOW FULL COLUMNS FROM `ls_nav` [ RunTime:0.002480s ]
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SHOW FULL COLUMNS FROM `ls_friendly_link` [ RunTime:0.000775s ]
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SHOW FULL COLUMNS FROM `ls_goods` [ RunTime:0.001393s ]
SELECT * FROM `ls_goods` WHERE `id` = 138817 AND `status` = 1 LIMIT 1 [ RunTime:0.000633s ]
UPDATE `ls_goods` SET `click_count` = 77 , `update_time` = 1752611936 WHERE `id` = 138817 [ RunTime:0.000585s ]
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SELECT * FROM `ls_goods` WHERE `del` = 0 AND `status` = 1 AND `create_time` <= 1752611877 ORDER BY `create_time` DESC LIMIT 5 [ RunTime:0.215606s ]

0.375547s

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