Reputation: 25
I have collection as below
"_id" : "PS8720_18",
"AlertID" : "18",
"Status" : "ACTIVE",
"triggerHistory" : [
{"triggerId" : "1535081507421"},
{"triggerId" : "1535105196735"},
{"triggerId" : "1535341330335"},
{"triggerId" : "1535364578821"}
]
I want to delete all element and just want keep last two entries in the array. Each document has different no of elements in array. How do I achieve this?
Upvotes: 1
Views: 37
Reputation: 332
Please Check with the following Query
db.getCollection('youtablename').update({}, {
$push: {
triggerHistory: {
$each: [ ],
$slice: -2
}
}},{multi:true})
Hope it Helps !!
Upvotes: 1