Is there an easy way to "$push" all fields of a document?
For example:
Say I have a Mongo collection of books:
{author: "tolstoy", title:"war & peace", price:100, pages:800}
{author: "tolstoy", title:"Ivan Ilyich", price:50, pages:100}
I'd like to group them by author - for each author, list his entire book objects:
{ author: "tolstoy",
books: [
{author: "tolstoy", title:"war & peace", price:100, pages:800}
{author: "tolstoy", title:"Ivan Ilyich", price:50, pages:100}
]
}
I can achieve this by explicitly pushing all fields:
{$group: {
_id: "$author",
books:{$push: {author:"$author", title:"$title", price:"$price", pages:"$pages"}},
}}
But is there any shortcut, something in the lines of:
// Fictional syntax...
{$group: {
_id: "$author",
books:{$push: "$.*"},
}}
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