MONGO CRUD Data Operators summary

Comparison

name	Description
$eq	Equals
$gt	Greater than
$gte	Greater than or equal
$lt	Less than
$lte	Less than or equal
$ne	Not equal to
$in	In the condition
$nin	Not in condition

Logic

name	Description
$or	Or
$and	And
$not	Non -
$nor	Neither, nor, Nor:[{name: ' Bugall ', age:12}], the name is not equal to ' bugall ', age is not equal to 12

Elements

name	Description
$exists	Whether the field exists
$type	field type of field

Array

name	Description
$all	Get all the data that meets the criteria
$elemMatch	Get all the data that meets the criteria below for a specific explanation
$size	If the return value is in the form of an array, define its return array element number

Note

name	Description
$comment	Add a description or remark to the command

》

$where

"this.credits == this.debits""obj.credits == obj.debits"returnreturn obj.credits == obj.debits; } } );

where接受字符串函数两种形式的参数，其中也提供了一些函数。

assert()BinData()DBPointer()DBRef()doassert()emit()gc()HexData()hex_md5()isNumber()isObject()ISODate()isString()Map()MD5()NumberInt()NumberLong()ObjectId()print()printjson()printjsononeline()sleep()Timestamp()tojson()tojsononeline()tojsonObject()UUID()version()

Attention:

因为用了$where后mongo生成的执行计划不能很好的利用索引，所以这里不建议大家使用$where

$all

选择满足条件的所有数据(documents)。

    { <field>: { $all: [ <value1> , <value2> ... ] } }

$all的功能是和$and的功能相同的，例如$and：

    { $and"ssl""security" } ] }

$and

    { $and"ssl""security" } ] }

$batchSize

db.inventory.find().batchSize(10)

控制返回结果的数据数量(多少条数据)，注意，在mongo shell里，batchSize()的设置并不会生效。同时distinct()也不会生效

$box

db.places.find( {   loc: { $geoWithin: { $box:  00100100 ] ] } }} )

定义一个"盒子"，2个点可以确定一个"盒子的位置"(我们把盒子理解为二维平面的矩形),那么上面这句话的意思就是找出在这个"盒子内的点",[22,22],[13,75],[19,24]这些值都将被返回

$center

    db.places.find(   { loc: { $geoWithin: { $center: [ [-7440.7410 ] } } })

返回所有在这个平面圆里的点(圆心坐标是(-74,40.74),圆半径是10)

$comment

    db.collection.find{ $query: { <query> }, $comment: <comment> } )

可以理解为为每一次执行加入一条备注，这些备注会被记录在profile里，有助于后期排错

$count

    55 } ).count()

计数

$distinct

    db.collection.distinct(field, query)

去重

$elemMatch

    { <field>: { $elemMatch: { <query1>, <query2>, ... } } }    1828588 ] }    2758889 ] }    db.scores.find(       8085 } } }    )

满足一区间

$exists

{field: {$exists: <boolean>}} db.records.find ({A: {$exists: true}}) Result: {A:5B:5, c:null} {a:3, B:null, C:8} {a:null, B:3C:9} {A:1B:2C:3} {A:2C:5} {A:3B:2} {A:4} db.records.find ({b: {$exists: false}}) Result: {A:2C:5} {A:4} {c:6}

$find

    ‘Los Pollos Hermanos‘ }).find(callback)

查找所有满足条件的数据

$findOne

    ‘Los Pollos Hermanos‘ }).find(callback)

返回一个满足条件的数据

$findAndModify

    {          findAndModify: <collection-name>,          query: <document>,          sort: <document>,          remove: <boolean>,          update: <document>,          new: <boolean>,          fields: <document>,          upsert: <boolean>    }

Field	Description
Query	a normal request statement may get more than one piece of data, but findandmodify will only process the first data
sort	because findandmodify can handle only one piece of data, we usually sort the data we get from query
Remove	If True removes the first data after query and defaults to False
update	update the first article after query
New	When set to True, returns the modified data instead of the original data, which defaults to False
fields	setting group
Upsert	When the value is true, the updated values are updated if they exist and are inserted if they do not exist. The default is False

db.people.findAndModify( {   "people",   "Gus""active"100 },   1 },   1 } },   upsert: true,   new : true} );

MONGO CRUD Data Operators summary