From ken-tanaka at genaris.co.jp  Wed Jun 25 21:34:39 2008
From: ken-tanaka at genaris.co.jp (=?ISO-2022-JP?B?GyRCRURDZiEhN3IwbE86GyhC?=)
Date: Thu, 26 Jun 2008 13:34:39 +0900
Subject: [Shibuya-pm] =?iso-2022-jp?b?REJJeDo6Q2xhc3MbJEIkSyREJCQkRjxBGyhC?=
 =?iso-2022-jp?b?GyRCTGQkNSQ7JEYkLyRAJDUkJBsoQg==?=
Message-ID: <48631C5F.9030404@genaris.co.jp>

Shibuya-pm ?????????

?????????????????????
???????????
DBIx::Class????????????(postgreSQL)????????????
?????????????
???????????join???????????????????????
??????????????SQL?DBIx::Class???????????????????

????????????????????????????????????
?????????
?????????SQL?????????

my @col=map("me.".$_,$sch->class('Professors')->columns);
my $hrC={
select=>'me.prof_ssn',
join=>{'work_ins'=>{'pid'=>{'work_projs'=>'grad_ssn'}}},
having=>{'count(work_projs.grad_ssn)'=>{'>=',5}},
group_by=>['me.prof_ssn'],
};
my $rsP = $sch->resultset('Professors')->search($hrQ,$hrC);
#print $rsP->count,"\n";

????????
486512566
248965255
090873519
141582651
????????????????ID????????
?????SQL??????
SELECT me.prof_ssn FROM professors me LEFT JOIN work_in work_ins ON (
work_ins.prof_ssn = me.prof_ssn ) JOIN project pid ON ( pid.pid =
work_ins.pid ) LEFT JOIN work_proj work_projs ON ( work_projs.pid =
pid.pid ) LEFT JOIN graduates grad_ssn ON ( grad_ssn.grad_ssn =
work_projs.grad_ssn ) GROUP BY me.prof_ssn HAVING (
count(work_projs.grad_ssn) >= 5 );
??????????
prof_ssn
------------
486512566
248965255
090873519
141582651
(4 rows)
??????????work_in?????professors?????project????
???relation??????? work_proj?????project?????
graduates???????relation???????

?????????????????????????????"count"???
????????????????????????????????????
??????????????????????
??????????????????having??????????????
????????
having?????????????????????????????????
???????????????????????????????????
?????postgreSQL???Perl???????????
?????????????????????????????????????
????????????????????????????????????
????????????
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