可以使用 .* 来模糊查询，如下是查询姓陈的用户。
db.customers.find( { name : /陈.*/i } );正则方式
最近有一监控业务，由于数据采集到非数字内容，导致监控图表无法正常显示，所以要找出这部分数据，进行删除，然后开发员从源头更正插入数据库的数据，不再产生非数字内容。
下面举一个例子：
建立测试数据：
for(i=1;i<=100;i++){db.test.insert({id:i,content:"test content",name:"wang"+i});}
> db.test.find()
{ "_id" : ObjectId("504ece595e8dc12ed97482b2"), "id" : 1, "content" : "test content", "name" : "wang1" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b3"), "id" : 2, "content" : "test content", "name" : "wang2" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b4"), "id" : 3, "content" : "test content", "name" : "wang3" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b5"), "id" : 4, "content" : "test content", "name" : "wang4" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b6"), "id" : 5, "content" : "test content", "name" : "wang5" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b7"), "id" : 6, "content" : "test content", "name" : "wang6" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b8"), "id" : 7, "content" : "test content", "name" : "wang7" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b9"), "id" : 8, "content" : "test content", "name" : "wang8" }
{ "_id" : ObjectId("504ece595e8dc12ed97482ba"), "id" : 9, "content" : "test content", "name" : "wang9" }
for(i=1;i<=101;i++){db.test.insert({id:i,content:666888,name:"joe"+i});}
> db.test.find({content:666888})
{ "_id" : ObjectId("504ececc5e8dc12ed9748316"), "id" : 1, "content" : 666888, "name" : "joe1" }
{ "_id" : ObjectId("504ececc5e8dc12ed9748317"), "id" : 2, "content" : 666888, "name" : "joe2" }
{ "_id" : ObjectId("504ececc5e8dc12ed9748318"), "id" : 3, "content" : 666888, "name" : "joe3" }
{ "_id" : ObjectId("504ececc5e8dc12ed9748319"), "id" : 4, "content" : 666888, "name" : "joe4" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831a"), "id" : 5, "content" : 666888, "name" : "joe5" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831b"), "id" : 6, "content" : 666888, "name" : "joe6" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831c"), "id" : 7, "content" : 666888, "name" : "joe7" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831d"), "id" : 8, "content" : 666888, "name" : "joe8" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831e"), "id" : 9, "content" : 666888, "name" : "joe9" }
通过模糊查询，查找相关数据：教学网 eduyo.com
> db.test.find({name:/joe/}) ---查询name字段含有joe的数据 等同于db.test.find({name:{$regex:'joe'}})
{ "_id" : ObjectId("504ececc5e8dc12ed9748316"), "id" : 1, "content" : 666888, "name" : "joe1" }
{ "_id" : ObjectId("504ececc5e8dc12ed9748317"), "id" : 2, "content" : 666888, "name" : "joe2" }
{ "_id" : ObjectId("504ececc5e8dc12ed9748318"), "id" : 3, "content" : 666888, "name" : "joe3" }
{ "_id" : ObjectId("504ececc5e8dc12ed9748319"), "id" : 4, "content" : 666888, "name" : "joe4" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831a"), "id" : 5, "content" : 666888, "name" : "joe5" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831b"), "id" : 6, "content" : 666888, "name" : "joe6" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831c"), "id" : 7, "content" : 666888, "name" : "joe7" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831d"), "id" : 8, "content" : 666888, "name" : "joe8" }
{ "_id" : ObjectId("504ececc5e8dc12ed974831e"), "id" : 9, "content" : 666888, "name" : "joe9" }
db.test.find({name:/joe/i}) 加了i，那么就不会区分大小写，都会显示，等同于db.test.find({name:{$regex:'joe',$options:'i'}})
db.test.find({name:/^joe/i}) ^匹配以joe开头的，而且不区分大小写
$type使用：
> db.test.find({content:{$type:2}}) --显示content是string的数据
{ "_id" : ObjectId("504ece595e8dc12ed97482b2"), "id" : 1, "content" : "test content", "name" : "wang1" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b3"), "id" : 2, "content" : "test content", "name" : "wang2" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b4"), "id" : 3, "content" : "test content", "name" : "wang3" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b5"), "id" : 4, "content" : "test content", "name" : "wang4" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b6"), "id" : 5, "content" : "test content", "name" : "wang5" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b7"), "id" : 6, "content" : "test content", "name" : "wang6" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b8"), "id" : 7, "content" : "test content", "name" : "wang7" }
{ "_id" : ObjectId("504ece595e8dc12ed97482b9"), "id" : 8, "content" : "test content", "name" : "wang8" }
{ "_id" : ObjectId("504ece595e8dc12ed97482ba"), "id" : 9, "content" : "test content", "name" : "wang9" }
> db.test.find({content:{$type:1}}) --显示content为double类型的
{ "_id" : ObjectId("504ecfcc5e8dc12ed974837b"), "id" : 1, "content" : 666888, "name" : "JOE1" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed974837c"), "id" : 2, "content" : 666888, "name" : "JOE2" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed974837d"), "id" : 3, "content" : 666888, "name" : "JOE3" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed974837e"), "id" : 4, "content" : 666888, "name" : "JOE4" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed974837f"), "id" : 5, "content" : 666888, "name" : "JOE5" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed9748380"), "id" : 6, "content" : 666888, "name" : "JOE6" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed9748381"), "id" : 7, "content" : 666888, "name" : "JOE7" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed9748382"), "id" : 8, "content" : 666888, "name" : "JOE8" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed9748383"), "id" : 9, "content" : 666888, "name" : "JOE9" }
{ "_id" : ObjectId("504ecfcc5e8dc12ed9748384"), "id" : 10, "content" : 666888, "name" : "JOE10" }
下面给出mongodb基于bson类型的列表：
| Type Description | Type value |
|---|---|
| Double | 1 |
| String | 2 |
| Object | 3 |
| Array | 4 |
| Binary data | 5 |
| Object id | 7 |
| Boolean | 8 |
| Date | 9 |
| Null | 10 |
| Regular expression | 11 |
| JavaScript code | 13 |
| Symbol | 14 |
| JavaScript code with scope | 15 |
| 32-bit integer | 16 |
| Timestamp | 17 |
| 64-bit integer | 18 |
| Min key | 255 |
| Max key | 127 |
根据以上方法找出相关数据，remove后，图表恢复正常
(责任编辑：ken)