CRUD操作

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insert

  • 正常插入：

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    > db.user.insert({x:1,y:2,z:3})
    WriteResult({ "nInserted" : 1 })

  • 循环插入

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    > for(var i=1;i<100;i++) db.user.insert({x:i, y:i*10, z:i*100})
    WriteResult({ "nInserted" : 1 })

update

  • 整个更新

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    > db.user.find()
    { "_id" : ObjectId("58d0d844bae387d0c1e8d870"), "x" : 1, "y" : 2 }
    { "_id" : ObjectId("58d0d84ebae387d0c1e8d871"), "x" : 2, "y" : 3 }
    > db.user.update({x:1},{x:999})
    WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
    > db.user.find()
    { "_id" : ObjectId("58d0d844bae387d0c1e8d870"), "x" : 999 }
    { "_id" : ObjectId("58d0d84ebae387d0c1e8d871"), "x" : 2, "y" : 3 }

  • 部分更新
    使用$set操作符

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    > db.user.find()
    { "_id" : ObjectId("58d0d844bae387d0c1e8d870"), "x" : 999 }
    { "_id" : ObjectId("58d0d84ebae387d0c1e8d871"), "x" : 2, "y" : 3 }
    > db.user.update({x:2},{$set:{x:999}})
    WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
    > db.user.find()
    { "_id" : ObjectId("58d0d844bae387d0c1e8d870"), "x" : 999 }
    { "_id" : ObjectId("58d0d84ebae387d0c1e8d871"), "x" : 999, "y" : 3 }

  • 不存在则创建

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    > db.user.find({x:1})
    > db.user.update({x:1},{x:2},true)
    WriteResult({
    	"nMatched" : 0,
    	"nUpserted" : 1,
    	"nModified" : 0,
    	"_id" : ObjectId("58d0da6e34123eac45d857ac")
    })
    > db.user.find()
    { "_id" : ObjectId("58d0d844bae387d0c1e8d870"), "x" : 999 }
    { "_id" : ObjectId("58d0d84ebae387d0c1e8d871"), "x" : 999, "y" : 3 }
    { "_id" : ObjectId("58d0da6e34123eac45d857ac"), "x" : 2 }

  • 更新多条
    mongodb默认是更新一条，据说是为了防止一时大意，
    而且更新多条不允许更新整个，只能使用$set关键字

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    > db.user.find()
    { "_id" : ObjectId("58d0dde9bae387d0c1e8d873"), "x" : 1, "y" : 2, "z" : 1 }
    { "_id" : ObjectId("58d0ddeabae387d0c1e8d874"), "x" : 1, "y" : 1, "z" : 1 }
    { "_id" : ObjectId("58d0ddebbae387d0c1e8d875"), "x" : 1, "y" : 1, "z" : 1 }
    > db.user.update({x:1},{$set:{y:2}},false,true)
    WriteResult({ "nMatched" : 3, "nUpserted" : 0, "nModified" : 2 })
    > db.user.find()
    { "_id" : ObjectId("58d0dde9bae387d0c1e8d873"), "x" : 1, "y" : 2, "z" : 1 }
    { "_id" : ObjectId("58d0ddeabae387d0c1e8d874"), "x" : 1, "y" : 2, "z" : 1 }
    { "_id" : ObjectId("58d0ddebbae387d0c1e8d875"), "x" : 1, "y" : 2, "z" : 1 }

remove

  • 删除某个collection所有内容

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    > db.user.remove({})
    WriteResult({ "nRemoved" : 102 })

  • 删除某个

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    > db.user.remove({x:3})
    WriteResult({ "nRemoved" : 1 })

find

  • 查找所有

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    > db.user.find()
    { "_id" : ObjectId("58d0cebcbae387d0c1e8d80a"), "username" : "zhangsan" }
    { "_id" : ObjectId("58d0d36abae387d0c1e8d80b"), "x" : 1, "y" : 2, "z" : 3 }
    { "_id" : ObjectId("58d0d37dbae387d0c1e8d80c"), "x" : 1, "y" : 2, "z" : 3 }

  • 有条件查找

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    > db.user.find({x:1})
    { "_id" : ObjectId("58d0d36abae387d0c1e8d80b"), "x" : 1, "y" : 2, "z" : 3 }
    { "_id" : ObjectId("58d0d37dbae387d0c1e8d80c"), "x" : 1, "y" : 2, "z" : 3 }

  • 查找总数目

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    > db.user.find().count()
    102

  • 分页,排序

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    > db.user.find().skip(5).limit(3).sort({x:1})
    { "_id" : ObjectId("58d0d453bae387d0c1e8d80f"), "x" : 3, "y" : 30, "z" : 300 }
    { "_id" : ObjectId("58d0d453bae387d0c1e8d810"), "x" : 4, "y" : 40, "z" : 400 }
    { "_id" : ObjectId("58d0d453bae387d0c1e8d811"), "x" : 5, "y" : 50, "z" : 500 }