this.find({}).populate({
path: "userId",
match: {name: "123123x"}
}).exec(callback);the associated query of two tables, and how to make the whole data not return when there is no data in the associated table
this.find({}).populate({
path: "userId",
match: {name: "123123x"}
}).exec(callback);the associated query of two tables, and how to make the whole data not return when there is no data in the associated table
use aggregate queries
db.projects.aggregate([{
$lookup:{
from:'users',
localField: 'userId',
foreignField: '_id',
as: 'userinfo'
}
},{
$match:{
'userinfo.sex': '0'
}},{"$unwind": "$remark"}])Previous: H5 video stream playback problem
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