（06）mongodb 游标与分页

叁歲伎倆 2021-11-01 07:03 220阅读 0赞

遍历1：

> var mycursor=db.person.find();  
> while(mycursor.hasNext())\{printjson(mycursor.next())\}  
\{ "\_id" : 1, "name" : "张三", "sex" : "男", "age" : 37.3 \}  
\{ "\_id" : 2, "name" : "张三", "sex" : "男", "age" : 27.3 \}  
\{ "\_id" : 3, "name" : "张三", "sex" : "男", "age" : 27.3 \}  
\{ "\_id" : 4, "name" : "李四", "class" : "三班", "score" : 90 \}  
\{ "\_id" : 5, "like" : "football", "name" : "王五" \}  
\{  
"\_id" : ObjectId("5d4190e8c21b717496b2989b"),  
"name" : "lisi",  
"age" : 13,  
"area" : "chaoyang",  
"gender" : "male"  
\}  
>

遍历2：

> var mycursor=db.person.find();  
> mycursor.forEach(function(obj)\{printjson(obj)\})  
\{ "\_id" : 1, "name" : "张三", "sex" : "男", "age" : 37.3 \}  
\{ "\_id" : 2, "name" : "张三", "sex" : "男", "age" : 27.3 \}  
\{ "\_id" : 3, "name" : "张三", "sex" : "男", "age" : 27.3 \}  
\{ "\_id" : 4, "name" : "李四", "class" : "三班", "score" : 90 \}  
\{ "\_id" : 5, "like" : "football", "name" : "王五" \}  
\{  
"\_id" : ObjectId("5d4190e8c21b717496b2989b"),  
"name" : "lisi",  
"age" : 13,  
"area" : "chaoyang",  
"gender" : "male"  
\}  
>

分页：(skip、limit)；

db.person.find().skip((n-1)\*m).limit(m); 查询第n页，每一页m条

> var mycursor=db.person.find().skip((1-1)\*2).limit(2);　　共两页，第一页  
> while(mycursor.hasNext())\{printjson(mycursor.next())\}  
\{ "\_id" : 1, "name" : "张三", "sex" : "男", "age" : 37.3 \}  
\{ "\_id" : 2, "name" : "张三", "sex" : "男", "age" : 27.3 \}  
>  
> var mycursor=db.person.find().skip((2-1)\*2).limit(2);　　共两页，第二页  
> while(mycursor.hasNext())\{printjson(mycursor.next())\}  
\{ "\_id" : 3, "name" : "张三", "sex" : "男", "age" : 27.3 \}  
\{ "\_id" : 4, "name" : "李四", "class" : "三班", "score" : 90 \}  
>

转载于:https://www.cnblogs.com/javasl/p/11279285.html