1

I am trying to extract JSON document subtree that's indexed by numerical key.

My JSON string:

{
    "pk": 20,
    "tree": {
        "100": {
            "values": [
                1, 2, 3
            ]
        },
        "abc" => 999
    }
}

My code:

$session = mysql_xdevapi\getSession("mysqlx://root:letmein@localhost");
$schema = $session->getSchema('test');
$coll = $schema->getCollection('myColl');
$expr = mysql_xdevapi\Expression('$.tree.*');
$result = $coll->find('$.pk=20')->fields(['$.tree[100]'])->execute();

Using '$.tree[100]' results in 

    [
        'tree' => null
    ]

Using '$.tree.*' results in

    [
        'tree' => [
            0 => [
                1, 2, 3
            ],
            1 => 999
        ]
    ]

Using '$.tree.abc' results in

    [
        'tree' => [
            'abc' => 999
        ]
    ]

So, '$.tree.abc' works, but '$.tree[100]' doesnt.

Question. How can I access values key using '$.tree[100]' expression?

Thanks!

temuri
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  • Try: `... $coll->find('$.pk=20')->fields(['$.tree."100"'])->execute();`. – wchiquito Jul 23 '19 at 17:37
  • nope: mysql_xdevapi\CollectionFind::fields(): Error while parsing, details: CDK Error: After seeing '$.tree."100" AS ', looking at '100': Expected identifier after AS (cdk:8). How would you do that search from Javascript mysqlsh? – temuri Jul 23 '19 at 17:43
  • Filed a bug report: https://bugs.php.net/bug.php?id=78331. – temuri Jul 24 '19 at 15:52
  • This works for me from mysqlsh-js: `mysqlsh-js> db.myColl.find("pk = 20").fields("tree.'100'");`. – wchiquito Jul 24 '19 at 20:57
  • Yes, it does. But only from mysqlsh. There's a bug in PHP extension. – temuri Jul 24 '19 at 21:42

1 Answers1

2

Thnx for report, following case:

$expr = mysql_xdevapi\Expression('$.tree."100"'); 
$result = $coll->find('$.pk=25')->fields($expr)->execute();

will be supported in mysql_xdevapi v8.0.18 which is planned for Oct 14.

marinesovitch
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