十四、mongoDB之find操作

忘是亡心i 2022-05-12 08:30 117阅读 0赞

\#                   mongoDB之find操作

<table> 
 <thead> 
  <tr> 
   <th align="center">运算符</th> 
   <th align="center">含义</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="center">find</td> 
   <td align="center">查询文档</td> 
  </tr> 
  <tr> 
   <td align="center">findAndModify</td> 
   <td align="center">查询和修改同时</td> 
  </tr> 
  <tr> 
   <td align="center">findOne</td> 
   <td align="center">查询一个，多个结果返回第一个</td> 
  </tr> 
  <tr> 
   <td align="center">findoneAndDelete</td> 
   <td align="center">查询并删除符合条件的</td> 
  </tr> 
  <tr> 
   <td align="center">findOneAndReplace</td> 
   <td align="center">查询并替换符合条件的</td> 
  </tr> 
  <tr> 
   <td align="center">findoneAndUpdate</td> 
   <td align="center">插入一个或者多个</td> 
  </tr> 
 </tbody> 
</table>

\`\`\` db.products.find( \{ qty: \{ $gt: 25 \} \} )

db.people.findAndModify(\{  
query: \{ name: “Tom”, state: “active”, rating: \{ $gt: 10 \} \},  
sort: \{ rating: 1 \},  
update: \{ $inc: \{ score: 1 \} \}  
\})

db.bios.findOne(  
\{ contribs: ‘OOP’ \},  
\{ \_id: 0, ‘name.first’: 0, birth: 0 \}  
)

db.scores.findOneAndDelete(  
\{ “name” : “M. Tagnum” \}  
)

//查询并替换符合条件的  
db.mycollection.findOneAndReplace(  
\{ “score” : \{ $lt : 20000 \} \},  
\{ “team” : “Observant Badgers”, “score” : 20000 \},  
\{ sort: \{ “score” : 1 \} \}  
)

//查询并更新  
db.scores.findOneAndUpdate(  
\{ “name” : “R. Stiles” \},  
\{ $inc: \{ “points” : 5 \} \}  
)