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SQL code
select count(DISTINCT id) from Policyinfo p where p.filename not in
(select p2.filename from Policyreadinfo p2 where p2.reader='test')
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"id", "select_type", "table","type","possible_keys","key","key_len","ref","rows","Extra"
"1", "PRIMARY", "p", "ALL", \N, \N, \N, \N, "1715","Using where"
"2", "DEPENDENT SUBQUERY","p2", "ALL", \N, \N, \N, \N, "4196","Using where"
ÆäÖбíPolicyinfo½á¹¹Îª
SQL code
CREATE TABLE `policyinfo` (
`id` int(11) NOT NULL auto_increment,
`filenum` varchar(50) default NULL,
`filename` varchar(100) default NULL,
`filecontent` longtext,
`writetime` datetime default NULL,
`writer` varchar(100) default NULL
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Policyreadinfo ±íµÄ½á¹¹ÊÇ
SQL code
CREATE TABLE `policyreadinfo` (
`id` int(11) NOT NULL auto_increment,
`filename` varchar(500) default NULL,
`reader` varchar(100) default NULL,
`readtime` datetime default NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
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ALTER TABLE policyreadinfo ADD `policyinfo_id` int(11);
-- ¸üÐÂpolicyreadinfo ±í£¬ÓÐЩ×Ö¶ÎΪnullÊÇÒòΪËû°ÑÕþ²ßÃû×Ö¸ÄÁË
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