So I'm kind of new to Mongo aggregations and after a lot of researching and googling I can't figure out how to do a particular query.
Say I have many documents with the following format:
{
_id: 1,
client: "Some Client",
type: "Some Type",
firstUsed: 2021-01-05T13:23:37.000+0000
lastUsed: 2021-05-05T18:11:23.000+0000
}
What I'm trying to do is group all the documents by type (for a particular client), and then get the first firstUsed datetime and the last lastUsed datetime.
I've been playing with aggregations but after doing a $match on the client, $group on the type, I can only figure out then how to get only one of the dates I need.
Sorting by firstUsed and getting the first document is fine, but then getting the last document doesnt mean I'm getting the correct lastUsed.
How do I re-sort and get the last lastUsed datetime while keeping the already found firstUsed?
Hope that makes sense,
Thanks
From what you said I think you are trying to get the earliest first date and the greatest last data. You can use $max and $min for the dates. Here's a solution that you can use:
{
$group: {
_id: "$type",
firstUsed: {
$min: "$firstUsed"
},
lastUsed: {
$max: "$lastUsed"
},
}
}