Question

我正在尝试编写一个脚本，它将从postgresql表读取数据并将其插入到oracle表中，这是我的脚本：

#!/usr/local/bin/perl

use strict;
use DBI;
use warnings FATAL => qw(all);

my $pgh = pgh(); # connect to postgres
my $ora = ora(); # connect to oracle
my @rows;
my $rows =[] ;
my $placeholders = join ", ", ("?") x @rows;

my $sth = $pgh->prepare('SELECT * FROM "Employees"');
$sth->execute();
 while (@rows = $sth->fetchrow_array()) {
    $ora->do("INSERT INTO employees VALUES($placeholders)");
 }

#connect to postgres
sub pgh {
my $dsn = 'DBI:Pg:dbname=northwind;host=localhost';
my $user = 'postgres';
my $pwd  = 'postgres';
my $pgh = DBI -> connect($dsn,$user,$pwd,{'RaiseError' => 1});
return $pgh;
}

#connect to oracle
sub ora {
my $dsn = 'dbi:Oracle:host=localhost;sid=orcl';
my $user = 'nwind';
my $pwd  = 'nwind';
my $ora = DBI -> connect($dsn,$user,$pwd,{'RaiseError' => 1});
return $ora;
}

我收到以下错误：

DBD::Oracle::db do failed: ORA-00936: missing expression (DBD ERROR: error possibly near <*> indicator at char 29 in 'INSERT INTO employees VALUES(<*>)') [for Statement "INSERT INTO employees VALUES()"] at /usr/share/perlproj/cgi-bin/scripts/nwind_pg2ora.pl line 19.

请帮我弄清楚我的代码。非常感谢！！汤妮雅。

Answer 1

请参阅DBD :: Oracle的文档，您必须绑定BLOB的参数值，如：

use DBD::Oracle qw(:ora_types); 
$sth->bind_param($idx, $value, { ora_type=>ORA_BLOB, ora_field=>'PHOTO' });

Answer 2

my @rows;
my $rows =[] ;

my $sth = $pgh->prepare('SELECT * FROM "Employees"');
$sth->execute();
while (@rows = $sth->fetchrow_array()) {
    my $placeholders = join ", ", ("?") x @rows;
    $ora->do("INSERT INTO employees VALUES($placeholders)");
}

您正在加入一个空的@rows来创建一个空的$占位符。在do（）之前执行while循环内的连接。

Answer 3

以下懒惰地创建一个语句句柄，用于根据返回记录中的列数插入Oracle数据库。

然后将这些列值插入到数据库中，所以很明显我们假设表结构是相同的：

use strict;
use DBI;
use warnings FATAL => qw(all);

my $pgh = pgh(); # connect to postgres
my $ora = ora(); # connect to oracle

my $sth = $pgh->prepare('SELECT * FROM "Employees"');
$sth->execute();

my $sth_insert;

while (my @cols = $sth->fetchrow_array()) {
    $sth_insert ||= do {
        my $placeholders = join ", ", ("?") x @cols;
        $ora->prepare("INSERT INTO employees VALUES ($placeholders)");
    };
    $sth_insert->execute(@cols);
}

Perl / DBI - 将Postgres中的行插入Oracle表

3 个答案: