将PostgreSQL数组转换为PHP数组

Question

我在PHP中阅读Postgresql数组时遇到问题.我尝试过explode(),但这打破了包含字符串逗号的数组和str_getcsv(),但它也没有用,因为PostgreSQL没有引用日语字符串.

不工作:

explode(',', trim($pgArray['key'], '{}'));
str_getcsv( trim($pgArray['key'], '{}') );

例:

// print_r() on PostgreSQL returned data: Array ( [strings] => {???, "some string without a comma", "a string, with a comma"} )

// Output: Array ( [0] => ??? [1] => "some string without a comma" [2] => "a string [3] => with a comma" ) 
explode(',', trim($pgArray['strings'], '{}'));

// Output: Array ( [0] => [1] => some string without a comma [2] => a string, with a comma ) 
print_r(str_getcsv( trim($pgArray['strings'], '{}') ));

Answer 1

如果您有PostgreSQL 9.2,您可以这样做:

SELECT array_to_json(pg_array_result) AS new_name FROM tbl1;

结果将数组作为JSON返回

然后在php方面问题:

$array = json_decode($returned_field);

你也可以转换回来.这是JSON函数页面

Answer 2

由于这些解决方案都不适用于多维数组,所以我在这里提供了一个适用于任何复杂数组的递归解决方案:

function pg_array_parse($s, $start = 0, &$end = null)
{
    if (empty($s) || $s[0] != '{') return null;
    $return = array();
    $string = false;
    $quote='';
    $len = strlen($s);
    $v = '';
    for ($i = $start + 1; $i < $len; $i++) {
        $ch = $s[$i];

        if (!$string && $ch == '}') {
            if ($v !== '' || !empty($return)) {
                $return[] = $v;
            }
            $end = $i;
            break;
        } elseif (!$string && $ch == '{') {
            $v = pg_array_parse($s, $i, $i);
        } elseif (!$string && $ch == ','){
            $return[] = $v;
            $v = '';
        } elseif (!$string && ($ch == '"' || $ch == "'")) {
            $string = true;
            $quote = $ch;
        } elseif ($string && $ch == $quote && $s[$i - 1] == "\\") {
            $v = substr($v, 0, -1) . $ch;
        } elseif ($string && $ch == $quote && $s[$i - 1] != "\\") {
            $string = false;
        } else {
            $v .= $ch;
        }
    }

    return $return;
}

我没有测试太多,但看起来它的工作原理.在这里你有我的测试结果:

var_export(pg_array_parse('{1,2,3,4,5}'));echo "\n";
/*
array (
  0 => '1',
  1 => '2',
  2 => '3',
  3 => '4',
  4 => '5',
)
*/
var_export(pg_array_parse('{{1,2},{3,4},{5}}'));echo "\n";
/*
array (
  0 => 
  array (
    0 => '1',
    1 => '2',
  ),
  1 => 
  array (
    0 => '3',
    1 => '4',
  ),
  2 => 
  array (
    0 => '5',
  ),
)
*/
var_export(pg_array_parse('{dfasdf,"qw,,e{q\"we",\'qrer\'}'));echo "\n";
/*
array (
  0 => 'dfasdf',
  1 => 'qw,,e{q"we',
  2 => 'qrer',
)
*/
var_export(pg_array_parse('{,}'));echo "\n";
/*
array (
  0 => '',
  1 => '',
)
*/
var_export(pg_array_parse('{}'));echo "\n";
/*
array (
)
*/
var_export(pg_array_parse(null));echo "\n";
// NULL
var_export(pg_array_parse(''));echo "\n";
// NULL

PS:我知道这是一个非常古老的帖子,但我找不到postgresql pre 9.2的任何解决方案

Answer 3

使用正则表达式将 PostgreSQL（一维）数组文字解析为 PHP 数组的可靠函数：

function pg_array_parse($literal)
{
    if ($literal == '') return;
    preg_match_all('/(?<=^\{|,)(([^,"{]*)|\s*"((?:[^"\\\\]|\\\\(?:.|[0-9]+|x[0-9a-f]+))*)"\s*)(,|(?<!^\{)(?=\}$))/i', $literal, $matches, PREG_SET_ORDER);
    $values = [];
    foreach ($matches as $match) {
        $values[] = $match[3] != '' ? stripcslashes($match[3]) : (strtolower($match[2]) == 'null' ? null : $match[2]);
    }
    return $values;
}

print_r(pg_array_parse('{blah,blah blah,123,,"blah \\"\\\\ ,{\100\x40\t\da?\?",NULL}'));
// Array
// (
//     [0] => blah
//     [1] => blah blah
//     [2] => 123
//     [3] =>
//     [4] => blah "\ ,{@@ da??
//     [5] =>
// )

var_dump(pg_array_parse('{,}'));
// array(2) {
//   [0] =>
//   string(0) ""
//   [1] =>
//   string(0) ""
// }

print_r(pg_array_parse('{}'));
var_dump(pg_array_parse(null));
var_dump(pg_array_parse(''));
// Array
// (
// )
// NULL
// NULL

print_r(pg_array_parse('{???, "some string without a comma", "a string, with a comma"}'));
// Array
// (
//     [0] => ???
//     [1] => some string without a comma
//     [2] => a string, with a comma
// )