push multiple items to non existing array mongodb code example

Example 1: mongodb add multiple element to array

db.students.update(
   { name: "joe" },
   { $push: { scores: { $each: [ 90, 92, 85 ] } } }
)

Example 2: insert item into list mongodb

db.col.update(
    { name: 'doc', 'list.id': 2 }, 
    {$push: {'list.$.items': {id: 5, name: 'item5'}}}
)