ask, there is only one piece of data in the users table. If I want to delete the indexes 8-11 in the middle cartList entry (array), how can I delete these field?
I"m not very good at learning mongoDB. By the way, what are the better mongoDB quick check materials ~ Thank you
db.users.update(
{ _id: ObjectId('58c41d5d3eddd93e9ab5b078') },
{
$push: {
cartList: {
$each: [ ],
$slice: 8
}
}
}
)buy a mongo book. Then cooperate with the information on the official website of mongo . Then in the actual use, constantly ask yourself some problems, and then find a solution.
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