pdo OPENJSON插入php无法正常工作（Azure SQL）

Normally this code works as a T-SQL script in Visual Studio except in T-SQL I add in:

declare @json nvarchar(MAX) = '{...}'

@json goes in the OPENJSON function

I am attempting to create a PHP script for the OPENJSON insert but this doesn't seem to work. I am a total beginner to all things Azure/SQL/PHP.

For reference on the OPENJSON function: https://blogs.msdn.microsoft.com/sqlserverstorageengine/2015/09/22/openjson-the-easiest-way-to-import-json-text-into-table/

<?php
    include_once("connection.php");
    $JSONrow = $_POST["jsonrow"];
    $table = $_POST["table"];
    $with = "(jobticketnumber nvarchar(50), contractor nvarchar(50),joblocation nvarchar(50), ...";

    $pdo_JSONinsert = $conn -> prepare('INSERT INTO '.$table.' SELECT * FROM OPENJSON('.$JSONrow.') WITH '.$with.'');
    $pdo_JSONinsert -> execute();

    $conn = null; 
?>

Thanks for the help!

Edit: error from PDO

<br />
<b>Fatal error</b>:  Uncaught PDOException: SQLSTATE[42000]: [Microsoft][ODBC Driver 13 for SQL Server]Syntax error, permission violation, or other nonspecific error in D:\home\site\wwwroot\insertrow.php:7
Stack trace:
#0 D:\home\site\wwwroot\insertrow.php(7): PDO-&gt;prepare('INSERT INTO job...')
#1 {main}
  thrown in 
<b>D:\home\site\wwwroot\insertrow.php</b> on line 
<b>7</b>
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