perl - DBD::Firebird 编码/解码

Question

在此示例中，Firebird 返回未解码的字符串。是我没有正确设置数据库还是 Firebird 就是这样工作的？

#!/usr/bin/env perl
use warnings;
use 5.10.0;
use utf8;
use open qw( :std :utf8 );
use Devel::Peek;
use DBI;

my ( $db, $dbh, $sth, @array );
my $table = 'test_encoding';
my $create = "CREATE TABLE $table ( name varchar(32) )";
my $insert = "INSERT INTO $table ( name ) VALUES ( ? )";
my $select = "SELECT * FROM $table";
my $value = 'ä';

$db = '/home/me/my_firebird_db';
$dbh = DBI->connect(
    "dbi:Firebird:db=$db", 'user', 'password',
    { PrintError => 0, RaiseError => 1, ib_charset => 'UTF-8' }
);
$sth = $dbh->do( "DROP TABLE $table" );
$sth = $dbh->do( $create );;
$sth = $dbh->prepare( $insert );
$sth->execute( $value );
@array = $dbh->selectrow_array( $select );
Dump $array[0];
say $array[0];
say "";

$db = '/home/me/my_sqlite_db';
$dbh = DBI->connect(
    "dbi:SQLite:db=$db", '', '',
    { PrintError => 0, RaiseError => 1, sqlite_string_mode => 5 }
);
$sth = $dbh->do( "DROP TABLE IF EXISTS $table" );
$sth = $dbh->do( $create );
$sth = $dbh->prepare( $insert );
$sth->execute( $value );
@array = $dbh->selectrow_array( $select );
Dump $array[0];
say $array[0];

输出:

SV = PV(0x2105360) at 0x22628a0
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x22a37e0 "\303\244"\0
  CUR = 2
  LEN = 10
ä

SV = PV(0x2111470) at 0x2121220
  REFCNT = 1
  FLAGS = (POK,pPOK,UTF8)
  PV = 0x1f2fed0 "\303\244"\0 [UTF8 "\x{e4}"]
  CUR = 2
  LEN = 10
ä

Answer 1

如 documentation of DBD::Firebird 的链接所示由 clamp 提供在评论中，您需要使用以下方式连接:

$dbh = DBI->connect(
    "dbi:Firebird:db=$db;ib_charset=UTF8", 'user', 'password',
    { PrintError => 0, RaiseError => 1, ib_enable_utf8 => 1 }

也就是说，ib_charset 属性必须位于连接字符串中，而不是散列中，并且其值必须为 UTF8(而不是 UTF-8!)，并且您需要添加 ib_enable_utf8 并设置 1 到哈希值。

具体来说，this part :

ib_enable_utf8 (driver-specific, boolean)

Setting this attribute to TRUE will cause any Perl Unicode strings supplied as statement parameters to be downgraded to octet sequences before passing them to Firebird.

Also, any character data retrieved from the database (CHAR, VARCHAR, BLOB sub_type TEXT) will be upgraded to Perl Unicode strings.

Caveat: Currently this is supported only if the ib_charset DSN parameter is UTF8. In the future, encoding and decoding to/from arbitrary character set may be implemented.

Example:

$dbh = DBI->connect( 'dbi:Firebird:db=database.fdb;ib_charset=UTF8',
    { ib_enable_utf8 => 1 } );