Question

I’ve got a document that looks like this:

{listName: 'LoremIpsum'
 listItems: [{productDescription: "", productImage: ""}...]}

How would I go about deleting an item from listItems if productImage didn’t exist?

I’ve tried the following with no result:

db.lists.update({"item.productImage":{$exists: false}}, {$unset:{"item":1}}, false, true )

Answer 1

Note that $pull can contain element matching criteria. As such this single update will remove the items that do not contain the field “productImage” :

db.lists.update({}, {$pull:{listItems:{productImage:{$exists:false}}}}, false, true)