> db.mediaCollection.find().skip().toArray()
[
{
"_id" : ObjectId("5353463193efef02c962da73"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind",
"Tracklist" : [
{
"Track" : "",
"Title" : "Smells like teen spirit",
"Length" : "5:02"
},
{
"Track" : "",
"Title" : "In Bloom",
"Length" : "4:15"
}
]
}
]
检索数据可以使用sort()方法来对数据进行排序，指定排序字段，并使用1或-1来指定排序方式是升序或降序。类似于SQL语句中的order by语句。
可以使用limit()方法来读取指定数量的数据，还可以使用skip()方法来跳过指定数量的数据。对分页性能上面效率非常高。
1. 语法
>db.COLLECTION_NAME.find().sort({KEY:1})
>db.COLLECTION_NAME.find().limit(NUMBER)
>db.COLLECTION_NAME.find().limit(NUMBER).skip(NUMBER)
2. sort()
> db.mediaCollection.find().sort({"Tracklist":}).toArray()
[
{
"_id" : ObjectId("5353462f93efef02c962da71"),
"Type" : "Book",
"Title" : "Definitive Guide to <a href="http://www.ttlsa.com/mongodb" title="mongodb"target="_blank">MongoDB</a>, the",
"ISBN" : "987-1-4302-3051-9",
"Publisher" : "Apress",
"Author" : [
"Membrey, Peter",
"Plugge, Eelco",
"Hawkins, Tim"
]
},
{
"_id" : ObjectId("5353462f93efef02c962da72"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind"
},
{
"_id" : ObjectId("5353463193efef02c962da73"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind",
"Tracklist" : [
{
"Track" : "",
"Title" : "Smells like teen spirit",
"Length" : "5:02"
},
{
"Track" : "",
"Title" : "In Bloom",
"Length" : "4:15"
}
]
}
]
> db.mediaCollection.find().toArray()
[
{
"_id" : ObjectId("5353462f93efef02c962da71"),
"Type" : "Book",
"Title" : "Definitive Guide to MongoDB, the",
"ISBN" : "987-1-4302-3051-9",
"Publisher" : "Apress",
"Author" : [
"Membrey, Peter",
"Plugge, Eelco",
"Hawkins, Tim"
]
},
{
"_id" : ObjectId("5353462f93efef02c962da72"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind"
},
{
"_id" : ObjectId("5353463193efef02c962da73"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind",
"Tracklist" : [
{
"Track" : "",
"Title" : "Smells like teen spirit",
"Length" : "5:02"
},
{
"Track" : "",
"Title" : "In Bloom",
"Length" : "4:15"
}
]
}
]
注意：如果指定的排序键不存在，那么数值将以它们插入的顺序升序返回。
3. limit()
该函数用来指定返回结果的最大数量。
> db.mediaCollection.find().limit().toArray()
[
{
"_id" : ObjectId("5353462f93efef02c962da71"),
"Type" : "Book",
"Title" : "Definitive Guide to MongoDB, the",
"ISBN" : "987-1-4302-3051-9",
"Publisher" : "Apress",
"Author" : [
"Membrey, Peter",
"Plugge, Eelco",
"Hawkins, Tim"
]
}
]
4. skip()
跳过前面两条数据。
> db.mediaCollection.find().skip().toArray()
[
{
"_id" : ObjectId("5353463193efef02c962da73"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind",
"Tracklist" : [
{
"Track" : "",
"Title" : "Smells like teen spirit",
"Length" : "5:02"
},
{
"Track" : "",
"Title" : "In Bloom",
"Length" : "4:15"
}
]
}
]
5. 组合使用
[
{
"_id" : ObjectId("5353462f93efef02c962da71"),
"Type" : "Book",
"Title" : "Definitive Guide to MongoDB, the",
"ISBN" : "987-1-4302-3051-9",
"Publisher" : "Apress",
"Author" : [
"Membrey, Peter",
"Plugge, Eelco",
"Hawkins, Tim"
]
},
{
"_id" : ObjectId("5353462f93efef02c962da72"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind"
},
{
"_id" : ObjectId("5353463193efef02c962da73"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind",
"Tracklist" : [
{
"Track" : "",
"Title" : "Smells like teen spirit",
"Length" : "5:02"
},
{
"Track" : "",
"Title" : "In Bloom",
"Length" : "4:15"
}
]
}
]
> db.mediaCollection.find().sort({"Tracklist":}).limit().skip().toArray()
[
{
"_id" : ObjectId("5353462f93efef02c962da72"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind"
}
]
6. 自然顺序$natural
> db.mediaCollection.find().sort( { $natural: - } ).toArray()
[
{
"_id" : ObjectId("5353463193efef02c962da73"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind",
"Tracklist" : [
{
"Track" : "",
"Title" : "Smells like teen spirit",
"Length" : "5:02"
},
{
"Track" : "",
"Title" : "In Bloom",
"Length" : "4:15"
}
]
},
{
"_id" : ObjectId("5353462f93efef02c962da72"),
"Type" : "CD",
"Artist" : "Nirvana",
"Title" : "Nevermind"
},
{
"_id" : ObjectId("5353462f93efef02c962da71"),
"Type" : "Book",
"Title" : "Definitive Guide to MongoDB, the",
"ISBN" : "987-1-4302-3051-9",
"Publisher" : "Apress",
"Author" : [
"Membrey, Peter",
"Plugge, Eelco",
"Hawkins, Tim"
]
}
]
转载至http://blog.fens.me/nodejs-mongoose-json/，