Change document value from string to ObjectId using Update Query
<p>I need to Update the Value of <code>Profession_id</code> from <strong>string</strong> to <strong>ObjectId</strong> for all document in a mongodb collection.</p>

<p>My Collection <strong>Profession</strong> is (Here I pasted only 2 Documents, in real I'm having more than 10K Documents)</p>

<pre><code>{
    "_id" : ObjectId("575845a713d284da0ac2ee81"),
    "Profession_id" : "575841b313d284da0ac2ee7d",
    "Prof_Name" : "Chief Officer"
}

{
    "_id" : ObjectId("575845d213d284da0ac2ee82"),
    "Profession_id" : "575841b313d284da0ac2ee7d",
    "Prof_Name" : "Executive Officer"
}
</code></pre>

<p>Kindly assist me how to update the value in MongoDB.</p>