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µØÖ·£º http://imysql.cn/taxonomy/term/1?page=1
[InnoDBϵÁÐ] -- innodb±íÈçºÎ¸ü¿ìµÃµ½count(*)½á¹û£ºhttp://imysql.cn/2008_06_24_speedup_innodb_count
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    -> username varchar(16) not null,
    -> userpassword varchar(32) not null
    -> );
create table log(
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update lcjd
set  `province` = substring_index( `province` , '<br>', '1' );
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set lc_name2 = concat('0', lc_name2)
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