将 postgresql hstore 转换为 php 数组

是否有一个好的 php 代码片段可以将 postgresql hstore 转换为 php 数组，它将正确地将 hstore 中未加引号的 NULL 转换为 php NULL？

EG：假设我们有以下 hstore 字符串：

"k1"=>"v1", "k2"=>NULL, "k3"=>"NULL", "k4"=>"\"v4"
(aka SELECT '"k1"=>"v1","k2"=>NULL,"k3"=>"NULL","k4"=>"\\"v4"'::hstore;)

我们如何将其转换为以下 php 数组？

array('k1' => 'v1', 'k2' => NULL, 'k3' => 'NULL', 'k4' => '\"v4');

我遵循以下转换器，但它似乎无法处理未加引号的 NULL：https://github.com/chanmix51/Pomm/blob/master/Pomm/Converter/PgHStore.php https://github.com/chanmix51/Pomm/blob/master/Pomm/Converter/PgHStore.php

我相信语法会是这样的：

$pdo = new PDO( /*connection string*/ );
// h is the hstore column.
$stmt = $pdo->query( "SELECT (each(h)).key, (each(h)).value FROM <table name>" );
$output = array();
foreach( $stmt->fetchAll( PDO::FETCH_NUM ) as $row )
{
   // $row[ 0 ] is the key, $row[ 1 ] is the value.
   $output[ $row[ 0 ] ] = $row[ 1 ];
}