MongoDB Beginner-Common basic commands

1, MongoDB official website download: https://www.mongodb.org/downloads can download the installation version and press release; temporarily select Unzip installation 2, cmd into the MongoDB installation directory under the bin, start MongoDB. Mongod Open the command while using--dbpath to specify the data storage location as "DB" folder. Mongod--dbpath=e:\study\db mongod--dbpath= E:\study\db--logpath= E:\study\db\ MongoDB.log--auth--port=27017--fork 3 , basic additions and deletions (1), shell operation input MONGO after performing the following actions
Show DBS; display a list of databases
Show collections; Displays a collection in the current database (similar to a table in a relational database) show users; show users; use myfirstdb; toggle \ Create Database
Db.help (); Database Common commands
Db.clonedatabase ("127.0.0.1"); Clones data from a database on a specified machine to the current database
Db.copydatabase ("MyDB", "temp", "127.0.0.1"), copy the native mydb data to the TEMP database
Collection Aggregation collection Operations
1. Create a Clustered collection (table)
Db.createcollection ("Collname", {size:20, capped:true, max:100}); #当为true时不能删除, or you can delete
2. Get a clustered collection with the specified name (table)
Db.getcollection ("account");
Db.getcollectionnames ();
3. Displays the status of all clustered indexes in the current DB
Db.printcollectionstats ();
User-related
1. Add a user
Db.createuser
Example: DB. CreateUser ({User: "Accountuser", pwd: "Password", roles: ["ReadWrite", "DbAdmin"]}) 2, delete user Db.dropuser ("UserName");
Detailed operation of aggregations (tables similar to relational databases) check: Db.dong.find (); #类似 select * from Dong; But you can set the size of the data displayed per page, using dbquery. shellbatchsize = 50; This results in 50 records per page. Default 20 with it iteration: Db.dong.save ({name: "Dong", age:26}); Add Data modification: db.dong.update ({age:26},{$set: {name: ' Zhou '}}); Similar: update Dong Set name = ' Zhou ' where age = 26; Delete: Db.dong.remove ({age:26}); Delete Age is 26 data (Db.dong. iscapped () True at that time cannot delete) for (Var i=0;i<20;i++) {Db.dong.save ({name: "Dong" +i,age:26+i})};
Some commonly used query commands: 2. Duplicate data db.userInfo.distinct ("name") of a column in the current clustered collection after the query is removed; Will filter out the same data in name equivalent to: Select Distict name from UserInfo; 3, Query age = 22 of the record Db.userInfo.find ({"Age": 22}); Equivalent to: SELECT * from userInfo where age = 22; 4. Check the age > 22 record Db.userInfo.find ({age: {$gt: 22}}); Equivalent to: SELECT * from UserInfo where >22; 5. Check the age < 22 record Db.userInfo.find ({age: {$lt: 22}}); Equivalent to: SELECT * from UserInfo where <22; 6, Query the age >= 25 record Db.userInfo.find ({age: {$gte: 25}}); Equivalent to: SELECT * from UserInfo where age >= 25; 7, Query the age <= 25 record Db.userInfo.find ({age: {$lte: 25}}); 8, query Age >= 23 and age <=-Db.userInfo.find ({age: {$gte: $, $lte: 26}}); 9, query name contains MONGO data Db.userInfo.find ({name:/mongo/}); Equivalent to a percent of select * from UserInfo where the name like '%mongo% '; 10. Query name Db.userInfo.find ({name:/^mongo/}) beginning with MONGO; SELECT * from UserInfo where name is like ' mongo% '; 11. Query the specified column name, age data Db.userInfo.find ({}, {name:1, age:1}); Equivalent to: Select Name, age from UserInfo; Of course name can also be used with true or false when using ture in case of River NAMe:1 effect, if you use False to exclude name, display column information other than name. 12. Query the specified column name, age data, age > Db.userInfo.find ({age: {$gt: +}}, {name:1, age:1}); Equivalent to: Select Name, age from UserInfo where age >25; 13. Sort Ascending by Age: Db.userInfo.find (). Sort ({age:1}); Descending: Db.userInfo.find (). Sort ({Age:-1}); 14. Query name = Zhangsan, age = 22 Data db.userInfo.find ({name: ' Zhangsan ', age:22}); Equivalent to: SELECT * from userInfo where name = ' Zhangsan ' and "age = ' 22 '; 15, query the first 5 data db.userInfo.find (). Limit (5); Equivalent: selecttop 5 * from UserInfo; 16, query 10 after the data Db.userInfo.find (). Skip (10); Equivalent to: SELECT * from UserInfo where ID not in (selecttop * from UserInfo); 17, query the data between 5-10 db.userInfo.find (). Limit (5). Can be used for pagination, limit is Pagesize,skip is the number of pages *pagesize 18, or with query Db.userInfo.find ({$or: [{age:22}, {age:25}]}); Equivalent to: SELECT * from UserInfo where is age = 25 19, query the first Data Db.userInfo.findOne (); Equivalent: Selecttop 1 * from UserInfo; Db.userInfo.find (). limit (1); 20. Query the number of record bars for a result set Db.userInfo.find ({age: {$gte: +}}). Count (); Equivalent to: SELECT COUNT (*) from useRinfo where age >= 20; 21. Count Db.userInfo.find ({sex: {$exists: true}}) in a column. Equivalent to: SELECT COUNT (Sex) from userInfo; Index 1, CREATE index Db.userInfo.ensureIndex ({name:1}); Db.userInfo.ensureIndex ({name:1, TS:-1}); 2, query the current aggregate collection all Indexes db.userInfo.getIndexes (); 3, view the total index record size db.userInfo.totalIndexSize (); 4, read all index information of the current collection Db.users.reIndex ();