mongodb数据操作(CRUD)
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1.数据插入
db.集合名.insert()
操作
> use hk switched to db hk > show collections > db.info.insert({"url":"www.lepu.cn"}) WriteResult({ "nInserted" : 1 }) > db.info.find() { "_id" : ObjectId("592bd4324c964b7784cca90f"), "url" : "www.lepu.cn" }
数组插入
db.info.insert([ {"url":"www.baidu.com"}, {"url":"www.9888.cn"}, {"url":"www.a.cn"} ]);
操作
> db.info.insert([ ... {"url":"www.baidu.com"}, ... {"url":"www.9888.cn"}, ... {"url":"www.a.cn"} ... ]); BulkWriteResult({ "writeErrors" : [ ], "writeConcernErrors" : [ ], "nInserted" : 3, "nUpserted" : 0, "nMatched" : 0, "nModified" : 0, "nRemoved" : 0, "upserted" : [ ] }) > db.info.find() { "_id" : ObjectId("592bd4324c964b7784cca90f"), "url" : "www.lepu.cn" } { "_id" : ObjectId("592bd4f84c964b7784cca910"), "url" : "www.baidu.com" } { "_id" : ObjectId("592bd4f84c964b7784cca911"), "url" : "www.9888.cn" } { "_id" : ObjectId("592bd4f84c964b7784cca912"), "url" : "www.a.cn" }
批量插入
for(var i=0;i<1000;i++){ db.info.insert({"url":"url->"+i}); }
操作
> for(var i=0;i<1000;i++){ ... db.info.insert({"url":"url->"+i}); ... } WriteResult({ "nInserted" : 1 }) > db.info.find() { "_id" : ObjectId("592bd4324c964b7784cca90f"), "url" : "www.lepu.cn" } { "_id" : ObjectId("592bd4f84c964b7784cca910"), "url" : "www.baidu.com" } { "_id" : ObjectId("592bd4f84c964b7784cca911"), "url" : "www.9888.cn" } { "_id" : ObjectId("592bd4f84c964b7784cca912"), "url" : "www.a.cn" } { "_id" : ObjectId("592bd5bf4c964b7784cca913"), "url" : "url->0" } { "_id" : ObjectId("592bd5bf4c964b7784cca914"), "url" : "url->1" } { "_id" : ObjectId("592bd5bf4c964b7784cca915"), "url" : "url->2" } ....................... { "_id" : ObjectId("592bd5bf4c964b7784cca921"), "url" : "url->14" } { "_id" : ObjectId("592bd5bf4c964b7784cca922"), "url" : "url->15" } Type "it" for more 在数据保存很多的情况下,只会显示20条,按it显示下一页
2.数据查询
关系运算,逻辑运算,数组运算,正则运算等
db.集合名称.find({查询条件},[{显示的字段}])
查询出url为"www.9888.cn"的数据
db.info.find({"url":"www.9888.cn"});
不需要显示的字段设为0,默认都是1
db.info.find({"url":"www.9888.cn"},{"_id":0,"url":1}) > db.info.find({"url":"www.9888.cn"},{"_id":0,"url":1}) { "url" : "www.9888.cn" }
格式化显示
pretty()
var data={ "name":"hkui", "age":26, "hobby":"footbal,music", "info":"it码农，哈哈哈哈哈哈哈" }; db.info.insert(data);
> db.info.find({"name":"hkui"}) { "_id" : ObjectId("592bda084c964b7784ccacfb"), "name" : "hkui", "age" : 26, "hobby" : "footbal,music", "info" : "it码农，哈哈哈哈哈哈哈" } > db.info.find({"name":"hkui"}).pretty() { "_id" : ObjectId("592bda084c964b7784ccacfb"), "name" : "hkui", "age" : 26, "hobby" : "footbal,music", "info" : "it码农，哈哈哈哈哈哈哈" }
关系查询
大于($gt)
小于($lt)
小于等于($lte)
大于等于($gte)
不等于($ne)
构造查询数据
db.stu.drop(); db.stu.insert({"name":"张三","sex":"男","age":18,"score":70,"address":"河南"}); db.stu.insert({"name":"李四","sex":"女","age":20,"score":60,"address":"山东"}); db.stu.insert({"name":"王五","sex":"男","age":17,"score":44,"address":"江苏"}); db.stu.insert({"name":"赵六","sex":"男","age":21,"score":80,"address":"山东"}); db.stu.insert({"name":"孙七","sex":"女","age":23,"score":50,"address":"湖北"}); db.stu.insert({"name":"tom","sex":"男","age":24,"score":20,"address":"海南"}); db.stu.insert({"name":"lucy","sex":"女","age":21,"score":62,"address":"浙江"}); db.stu.insert({"name":"jack","sex":"男","age":20,"score":90,"address":"美国"}); db.stu.insert({"name":"smith","sex":"男","age":19,"score":88,"address":"美国"});
db.stu.find({"name":"tom"}).pretty(); db.stu.find({"address":"山东"}).pretty(); age大于20的 db.stu.find({"age":{"$gt":20}}).pretty(); 查询姓名不是tom的 db.stu.find({"name":{"$ne":"tom"}}).pretty();
逻辑运算
与($and)
或($or)
非($not,$nor)
查询年龄在18~21 db.stu.find({"age":{"$gte":18,"$lte":21}}) 查询年龄小于20或者score>80的 db.stu.find({"$or": [ {"age":{"$lt":20}}, {"score":{"$gt":80}} ] }).pretty();
取反操作 db.stu.find({"$nor": [ {"age":{"$lt":22}}, {"score":{"$gt":90}} ] }).pretty();
取模
$mod {$mod:[数字,余数]} 取出除数是20,,余数为1的 db.stu.find({"age":{"$mod":[20,1]}}).pretty(); 范围查询 $in或者$nin db.stu.find({ "address":{"$in":["河南","山东"]} })
数组查询
针对数组内容,运算符有
$all,$size,$slice,$elemMath
构造数据
db.stus.drop(); db.stus.insert({"name":"hk1","sex":"男","age":18,"score":70,"address":"河南","course_id":[1,2,3,4,5]}); db.stus.insert({"name":"hk2","sex":"女","age":20,"score":60,"address":"山东","course_id":[1,2,3,4]}); db.stus.insert({"name":"hk3","sex":"男","age":17,"score":44,"address":"江苏","course_id":[1,2,3]}); db.stus.insert({"name":"hk4","sex":"男","age":21,"score":80,"address":"山东","course_id":[1,3]}); db.stus.insert({"name":"hk5","sex":"女","age":23,"score":50,"address":"湖北","course_id":[2,3,4]}); db.stus.insert({"name":"tom","sex":"男","age":24,"score":20,"address":"海南","course_id":[1]}); db.stus.insert({"name":"lucy","sex":"女","age":21,"score":62,"address":"浙江","course_id":[3,4]}); db.stus.insert({"name":"jack","sex":"男","age":20,"score":90,"address":"美国","course_id":[1,2,3,4]}); db.stus.insert({"name":"smith","sex":"男","age":19,"score":88,"address":"美国","course_id":[2,4]});
查询同事参加 2,4课程的
db.stus.find({"course_id":{"$all":[2,4]}}).pretty();
db.stus.find({"address":{"$all":["河南","山东"]}}).pretty();
//无结果
db.stus.find({"address":{"$all":["河南"]}}).pretty();
//查出了家是河南的
索引操作(从0 开始)
第二个为4的
db.stus.find({"course_id.1":4}).pretty();
//只参加2门课程的 db.stus.find({"course_id":{"$size":2}}).pretty(); //数组截取 //取前2门 db.stus.find({"age":18},{"course_id":{"$slice":2}}).pretty(); //1,2 //后2门 db.stus.find({"age":18},{"course_id":{"$slice":-2}}).pretty();//4,5 db.stus.find({"age":18},{"course_id":{"$slice":[1,2]}}).pretty();//2,3 db.stus.find({"age":18},{"course_id":{"$slice":[3,1]}}).pretty();//4 //闭合区间，长度
$elemMatch
数据
db.stus1.drop(); db.stus1.insert({"name":"hk1","sex":"男","age":18,"score":70,"address":"河南","course_id":[1,2,3,4,5], "parents":[ {"name":"hk1_father","job":"程序员","age":50}, {"name":"hk1_mother","job":"工人","age":45} ] }); db.stus1.insert({"name":"hk2","sex":"女","age":20,"score":60,"address":"山东","course_id":[1,2,3,4], "parents":[ {"name":"hk2_father","job":"教师","age":52}, {"name":"hk2_mother","job":"程序员","age":45} ] }); db.stus1.insert({"name":"hk3","sex":"男","age":17,"score":44,"address":"江苏","course_id":[1,2,3], "parents":[ {"name":"hk3_father","job":"教授","age":45}, {"name":"hk3_mother","job":"销售","age":40} ] }); db.stus1.insert({"name":"hk4","sex":"男","age":21,"score":80,"address":"山东","course_id":[1,3]});
查询出age大于18,父母里有是程序员的 db.stus1.find({ "$and": [ { "age":{"$gt":18}}, { "parents":{ "$elemMatch": {"job":"程序员"} } } ] }).pretty(); 查询出age大于18,父母里有是程序员的而且程序员年龄小于50 db.stus1.find({ "$and": [ { "age":{"$gt":18}}, { "parents":{ "$elemMatch": {"$and": [{"job":"程序员"},{"age":{"$lt":50}}] } } } ] }).pretty();
判断某个字段是否存在 $exists
true表示存在,false表示不存在
判断没有父母信息存在的
db.stus.find({"parents":{"$exists":true}}).pretty(); db.stus.find({"parents":{"$exists":false}}).pretty();
条件过滤
$where
查询年龄大于20的 db.stu.find({"$where":"this.age>20"}); db.stu.find("this.age>20");
每一行进行判断
或者
db.stu.find(function(){ return this.age>20; })
或者
db.stu.find({"$where":function(){
return this.age>20;
}});
复合条件判断
db.stu.find({"$and":[
{"$where":"this.age>20"},
{"$where":"this.age<22"},
]});
缺点把bson变成js代码语法结构,这种方式不方便使用数据库索引机制
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