查询和计划操作符
一、评价查询操作符
| 方法名 | 描述 |
|---|---|
| $mod | 取模计算 |
| $regex | 模糊查询，查询该字段包含某个字符串 |
| $text | 对有text索引的字段进行模糊查询 |
| $where | 使用js代码查询数据 |
1、使用$mod进行模运算查询
c1的数据集如下：
> db.c1.find()
{ "_id" : ObjectId("5f97bb1a0436fe0f6dbb0526"), "age" : 1, "length" : 30 }
{ "_id" : ObjectId("5f97bb200436fe0f6dbb0527"), "age" : 7, "length" : 30 }
{ "_id" : ObjectId("5f97bb260436fe0f6dbb0528"), "age" : 8, "length" : 30 }
{ "_id" : ObjectId("5f97bb860436fe0f6dbb052a"), "age" : 13, "length" : 30 }
取年龄模6结果为1的数据
> db.c1.find({age:{$mod:[6,1]}})
{ "_id" : ObjectId("5f97bb1a0436fe0f6dbb0526"), "age" : 1, "length" : 30 }
{ "_id" : ObjectId("5f97bb200436fe0f6dbb0527"), "age" : 7, "length" : 30 }
{ "_id" : ObjectId("5f97bb860436fe0f6dbb052a"), "age" : 13, "length" : 30 }
2、使用$regex进行模糊查询
c2的数据集如下：
> db.c2.find()
{ "_id" : ObjectId("5f97bc460436fe0f6dbb052b"), "name" : "小明", "age" : 20 }
{ "_id" : ObjectId("5f97bc4c0436fe0f6dbb052c"), "name" : "小刚", "age" : 20 }
{ "_id" : ObjectId("5f97bc570436fe0f6dbb052d"), "name" : "小明明", "age" : 20 }
{ "_id" : ObjectId("5f97bc5f0436fe0f6dbb052e"), "name" : "大明", "age" : 20 }
查name中包含“明”的数据：
> db.c2.find({name:{"$regex":"明"}}))
{ "_id" : ObjectId("5f97bc460436fe0f6dbb052b"), "name" : "小明", "age" : 20 }
{ "_id" : ObjectId("5f97bc570436fe0f6dbb052d"), "name" : "小明明", "age" : 20 }
{ "_id" : ObjectId("5f97bc5f0436fe0f6dbb052e"), "name" : "大明", "age" : 20 }
3、使用$text对有text索引的字段进行模糊查询
先对c4添加索引：
> db.c4.createIndex( { subject: "text" } )
c4的数据集如下：
> db.c4.find( )
{ "_id" : 1, "subject" : "hello world", "title" : "hello" }
{ "_id" : 2, "subject" : "hello python", "title" : "python" }
{ "_id" : 3, "subject" : "hello java", "title" : "java" }
{ "_id" : 4, "subject" : "hello mongodb", "title" : "mongodb" }
{ "_id" : 5, "subject" : "中文", "title" : "mongodb" }
使用"$text"进行查询
> db.c4.find({"$text":{"$search":"world"}})
{ "_id" : 1, "subject" : "hello world", "title" : "hello" }
4、使用$where进行查询
c5的数据集如下：
> db.c5.find()
{ "_id" : ObjectId("5f98df8e4262ff84adb202d5"), "a" : { "a" : 1 }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98df9c4262ff84adb202d6"), "a" : { "a" : 1, "b" : "1" }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98df9f4262ff84adb202d7"), "a" : { "a" : 1, "b" : "2" }, "b" : 2, "c" : 3 }
查询某条内嵌文档中a的值跟b的值相等的数据：
> db.c5.find({$where:"this.a.a==this.a.b"})
{ "_id" : ObjectId("5f98df9c4262ff84adb202d6"), "a" : { "a" : 1, "b" : "1" }, "b" : 2, "c" : 3 }
二、逻辑查询操作符
| 方法 | 描述 |
|---|---|
| $and | 并且，两个条件同时成立 |
| $nor | 两个条件同时不成立 |
| $not | 不是某个值 |
| $or | 或者，两个条件只成立一个 |
c6的数据集如下：
> db.c6.find()
{ "_id" : ObjectId("5f98e4217c6aa7043a43d2f8"), "subject" : "hello world", "title" : "hello" }
{ "_id" : ObjectId("5f98e4297c6aa7043a43d2f9"), "subject" : "hello python", "title" : "hello" }
{ "_id" : ObjectId("5f98e42e7c6aa7043a43d2fa"), "subject" : "hello java", "title" : "hello" }
1、使用$and进行查询
查询subject为hello java,title为hello的文档
> db.c6.find({$and:[{"subject":"hello java"},{"title":"hello"}]})
{ "_id" : ObjectId("5f98e42e7c6aa7043a43d2fa"), "subject" : "hello java", "title" : "hello" }
2、使用$nor进行查询
查询subject不为hello java并且title不为hel的文档
> db.c6.find({$nor:[{"subject":"hello java"},{"title":"hel"}]})
{ "_id" : ObjectId("5f98e4217c6aa7043a43d2f8"), "subject" : "hello world", "title" : "hello" }
{ "_id" : ObjectId("5f98e4297c6aa7043a43d2f9"), "subject" : "hello python", "title" : "hello" }
3、使用$not进行查询
查询b不小于2的值
> db.c5.find({b:{$not:{$lt:2}}})
{ "_id" : ObjectId("5f98df8e4262ff84adb202d5"), "a" : { "a" : 1 }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98df9c4262ff84adb202d6"), "a" : { "a" : 1, "b" : "1" }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98df9f4262ff84adb202d7"), "a" : { "a" : 1, "b" : "2" }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98e0674262ff84adb202d8"), "a" : { "a" : 1, "b" : 1 }, "b" : 2, "c" : 3 }
4、使用$or进行查询
查询b为2或者c为4的值
> db.c5.find({$or:[{b:2},{c:4}]})
{ "_id" : ObjectId("5f98df8e4262ff84adb202d5"), "a" : { "a" : 1 }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98df9c4262ff84adb202d6"), "a" : { "a" : 1, "b" : "1" }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98df9f4262ff84adb202d7"), "a" : { "a" : 1, "b" : "2" }, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("5f98e0674262ff84adb202d8"), "a" : { "a" : 1, "b" : 1 }, "b" : 2, "c" : 3 }
三、比较查询操作符
| 方法 | 描述 |
|---|---|
| $gt | 大于 |
| $gte | 大于等于 |
| $lt | 小于 |
| $lte | 小于等于 |
| $in | 在…之中 |
| $nin | 不在…之中 |
| $ne | 不等于 |
| $eq | 等于 |
c7的数据集如下
> db.c7.find()
{ "_id" : 1, "age" : 20, "length" : 17 }
{ "_id" : 2, "age" : 23, "length" : 17 }
{ "_id" : 3, "age" : 24, "length" : 17 }
{ "_id" : 4, "age" : 19, "length" : 17 }
1、$gt查询年龄大于20的
> db.c7.find({age:{$gt:20}})
{ "_id" : 2, "age" : 23, "length" : 17 }
{ "_id" : 3, "age" : 24, "length" : 17 }
2、$gte查询年龄大于等于20的
> db.c7.find({age:{$gte:20}})
{ "_id" : 1, "age" : 20, "length" : 17 }
{ "_id" : 2, "age" : 23, "length" : 17 }
{ "_id" : 3, "age" : 24, "length" : 17 }
3、$lt查询年龄小于20的
> db.c7.find({age:{$lt:20}})
{ "_id" : 4, "age" : 19, "length" : 17 }
4、$lte查询年龄小于等于20的
> db.c7.find({age:{$lte:20}})
{ "_id" : 1, "age" : 20, "length" : 17 }
{ "_id" : 4, "age" : 19, "length" : 17 }
5、$in查询年龄在20,21,22之中的
> db.c7.find({age:{$in:[20,21,22]}})
{ "_id" : 1, "age" : 20, "length" : 17 }
6、$nin查询年龄不在20,21,22之中的
> db.c7.find({age:{$nin:[20,21,22]}})
{ "_id" : 2, "age" : 23, "length" : 17 }
{ "_id" : 3, "age" : 24, "length" : 17 }
{ "_id" : 4, "age" : 19, "length" : 17 }
7、$ne查询年龄不等于20的
> db.c7.find({age:{$ne:20}})
{ "_id" : 2, "age" : 23, "length" : 17 }
{ "_id" : 3, "age" : 24, "length" : 17 }
{ "_id" : 4, "age" : 19, "length" : 17 }
8、$eq查询年龄等于20的
> db.c7.find({age:{$eq:20}})
{ "_id" : 1, "age" : 20, "length" : 17 }
四、数组查询操作符
| 方法 | 描述 |
|---|---|
$all | 匹配数组中包含某个数组的所有数据 |
$size | 匹配数组长度为某个数的数据 |
$elemMatch | 查询数组中至少有一个元素满足所有指定条件的文档 |
| $slice | 对数组返回的值切片 |
c8的数据集如下：
> db.c8.find()
{ "_id" : ObjectId("5f992b2b7c6aa7043a43d2fb"), "name" : "zs", "score" : [ 10, 80, 90 ] }
{ "_id" : ObjectId("5f992b347c6aa7043a43d2fc"), "name" : "yz", "score" : [ 70, 80, 90 ] }
{ "_id" : ObjectId("5f992b407c6aa7043a43d2fd"), "name" : "lh", "score" : [ 70, 85, 92 ] }
{ "_id" : ObjectId("5f992b497c6aa7043a43d2fe"), "name" : "llx", "score" : [ 79, 85, 92 ] }
{ "_id" : ObjectId("5f992e637c6aa7043a43d2ff"), "name" : "xm", "score" : [ 79, 85 ] }
1、$all查询score包含[70,80]的数据
> db.c8.find({score:{$all:[70,80]}})
{ "_id" : ObjectId("5f992b347c6aa7043a43d2fc"), "name" : "yz", "score" : [ 70, 80, 90 ] }
2、$size查询score长度为3数据
> db.c8.find({score:{$size:2}})
{ "_id" : ObjectId("5f992e637c6aa7043a43d2ff"), "name" : "xm", "score" : [ 79, 85 ] }
3、$elemMatch查询数组中至少有一个元素满足所有指定条件的文档
查询score中至少有一个介于80和60之间
> db.c8.find({score:{$elemMatch:{$lt:80,$gt:60}}})
{ "_id" : ObjectId("5f992b347c6aa7043a43d2fc"), "name" : "yz", "score" : [ 70, 80, 90 ] }
{ "_id" : ObjectId("5f992b407c6aa7043a43d2fd"), "name" : "lh", "score" : [ 70, 85, 92 ] }
{ "_id" : ObjectId("5f992b497c6aa7043a43d2fe"), "name" : "llx", "score" : [ 79, 85, 92 ] }
{ "_id" : ObjectId("5f992e637c6aa7043a43d2ff"), "name" : "xm", "score" : [ 79, 85 ] }
4、查询数组第一个值为70的数据
> db.c8.find({"score.0":70})
{ "_id" : ObjectId("5f992b347c6aa7043a43d2fc"), "name" : "yz", "score" : [ 70, 80, 90 ] }
{ "_id" : ObjectId("5f992b407c6aa7043a43d2fd"), "name" : "lh", "score" : [ 70, 85, 92 ] }
五、元查询操作符
| 方法名 | 描述 |
|---|---|
| $type | 数据类型操作符 |
| $exists | 判断字段是否存在，1为存在，0为不存在 |
1、$type查询数据为某个类型的数据
| 类型 | 数字 | 备注 |
|---|---|---|
| Double | 1 | |
| String | 2 | |
| Object | 3 | |
| Array | 4 | |
| Binary data | 5 | |
| Undefined | 6 | 已废弃。 |
| Object id | 7 | |
| Boolean | 8 | |
| Date | 9 | |
| Null | 10 | |
| Regular Expression | 11 | |
| JavaScript | 13 | |
| Symbol | 14 | |
| JavaScript (with scope) | 15 | |
| 32-bit integer | 16 | |
| Timestamp | 17 | |
| 64-bit integer | 18 | |
| Min key | 255 | Query with -1。 |
| Max key | 127 |
c9的数据集为：
> db.c9.find()
{ "_id" : ObjectId("5f993d7b7c6aa7043a43d300"), "name" : "zs", "age" : 20 }
{ "_id" : ObjectId("5f993d847c6aa7043a43d301"), "name" : "ls", "age" : "20" }
{ "_id" : ObjectId("5f993e247c6aa7043a43d302"), "name" : "ww", "age" : 20, "score" : 95 }
查询age为字符串类型的数据
> db.c9.find({age:{"$type":2}})
{ "_id" : ObjectId("5f993d847c6aa7043a43d301"), "name" : "ls", "age" : "20" }
2、$exists查询某个字段存在的数据
> db.c9.find({score:{$exists:1}})
{ "_id" : ObjectId("5f993e247c6aa7043a43d302"), "name" : "ww", "age" : 20, "score" : 95 }
> db.c9.find({score:{$exists:0}})
{ "_id" : ObjectId("5f993d7b7c6aa7043a43d300"), "name" : "zs", "age" : 20 }
{ "_id" : ObjectId("5f993d847c6aa7043a43d301"), "name" : "ls", "age" : "20" }