我面对一个很奇怪的情况。通过perl脚本我连接到Postgresql数据库,我从具体表中选择特定的列。来自DB的SELECT查询的输出保存到File中。当第二次执行脚本时,来自第一个选择的文件的内容被移动到另一个文件,并且实际文件被新的选择输出填充。然后我比较这两个文件。它们应该在两次脚本执行时相同。问题是,当我运行两次脚本进行比较时,它们在一行中不同,当我第三次执行脚本时,输出与第一次相同,当我执行第四次时,输出是相同的和第二次一样,这些输出反复交替出现。我尝试了4种不同的方法,如何从表中获取选定的行,但仍然是相同的情况,但是,数据库中表的内容仍然是相同的。
请参阅以下代码:
use strict;
use warnings;
use DBI;
use DBD::Pg;
use File::Copy;
use File::Compare;
use List::Compare;
use MIME::Lite;
use Data::Dumper;
use Sys::Hostname;
my $qry1 = "select id, name from nms_incident_config where enable = 'f' order by name asc";
my $ltraps = '/tmp/traps.list' ;
my $ntraps = '/opt/tools/trapcfg_check/actual_traps.list';
if(-e $ntraps ) {
print "Actual trap list exists \n";
move("$ntraps","$ltraps") or die "Copy failed! :$!";
};
open my $out ,">", "/opt/tools/trapcfg_check/actual_traps.list";
#connect to db and run selects for further use
my $db = DBI->connect( "dbi:Pg:dbname=<db_name>;host=localhost;","postgres", "*******", {'RaiseError' => 1});
my $qry1s = $db-> prepare("$qry1");
$qry1s->execute();
方法1
while (my @row = $qry1s -> fetchrow_array()) {
$" = ",";
print $out "@row \n";
}
方法2
while (my @row = $qry1s->fetchrow_array()) {
#print $out "$row[0],$row[1]\n";
print $out join(", ", @row), "\n"
}
方法3
my ($id,$name);
$qry1s->bind_columns(\($id, $name));
while ($qry1s->fetch){
print $out "$id, $name\n"
}
方法4
my $row;
$row = $qry1s->fetchall_arrayref([]);
foreach my $r (@{$row})
{
print $out join(", ", @{$r}), "\n";
}
在脚本中,只有一个方法被取消注释并被使用,其余的被注释。
$db->disconnect();
open F ,"</opt/tools/trapcfg_check/actual_traps.list" or die $!;
open F1 , "/tmp/traps.list" or die $!;
my @ntraps=<F>;
my @ltraps=<F1>;
my @lonly ;
my @nonly ;
if ( compare( $ltraps,$ntraps ) == 0 ) {
print "Files are same \n" ;
die "Files are same\n";
};
if ( compare( $ltraps,$ntraps ) ne 0 ) { print "Files are different\n";
my $tc = List::Compare->new(\@ltraps, \@ntraps );
@lonly = $tc->get_complement;
# @nonly = $tc->get_unique;
print "Different row/s in new trap list: "."@lonly\n";
};
输出&gt;
# ./tcheck_2.pl
Actual trap list exists
Files are same
Files are same
# cat /opt/tools/trapcfg_check/actual_traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecureAP
# cat /tmp/traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecur
# ./tcheck_2.pl
Actual trap list exists
Files are different
Different row/s in new trap list: 2147590214, wlsxStaUnAssociatedFromUnsecur
# cat /opt/tools/trapcfg_check/actual_traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecur
# cat /tmp/traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecureAP
# ./tcheck_2.pl
Actual trap list exists
Files are same
Files are same
# cat /opt/tools/trapcfg_check/actual_traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecureAP
# cat /tmp/traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecur
# ./tcheck_2.pl
Actual trap list exists
Files are different
Different row/s in new trap list: 2147590214, wlsxStaUnAssociatedFromUnsecur
# cat /opt/tools/trapcfg_check/actual_traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecur
# cat /tmp/traps.list | grep -i 2147590214
2147590214, wlsxStaUnAssociatedFromUnsecureAP
你能帮帮我吗? :)
感谢
最诚挚的问候 哈罗