> db.runCommand(
{
	"create": "collectionName",
	"validator": { /* $query document. (Almost) all $query operators allowed*/
		"fieldName": {
			"$gte": 1024
		}
	},
	/* (default: "" == "strict") */
	"validationLevel": "", /* "" | "strict" | "off" | "moderate" */
	/*  (default: "" == "error") */
	"validationAction": "" /* "" | "error" | "warn" */
})

{ "ok" : 1 }

> db.existingCollectionName.insert({"my": "document"})
WriteResult({ "nInserted" : 1 })
> db.runCommand(
{
	"collMod": "existingCollectionName",
	"validator": { /* Same $query document as for the 'create' command */
		"fieldName": {
			"$gte": 1024
		}
	},
	/* (default: "" == "strict") */
	"validationLevel": "", /* "" | "strict" | "off" | "moderate" */
	/*  (default: "" == "error") */
	"validationAction": "" /* "" | "error" | "warn" */
})

{ "ok" : 1 }

> db.runCommand(
{
	"listCollections": 1,
	"filter": {
		"name": "collectionName"
	}
})

{
	"cursor" : {
		"id" : NumberLong(0),
		"ns" : "test.$cmd.listCollections",
		"firstBatch" : [
			{
				"name" : "collectionName",
				"options" : {
					"validator" : {
						"fieldName" : {
							"$gte" : 1024
						}
					}
				}
			}
		]
	},
	"ok" : 1
}