Command comparison between mongodb and mysql _ MySQL

We always see our advantages and disadvantages in the comparison, which is the same for mongodb. the comparison study allows us to master the basic knowledge about mongodb as soon as possible. Comparison between mongodb and mysql commands relational databases generally refer to databases and tables. we always see their advantages and disadvantages in comparison, which is the same for mongodb, compared and learned, we can learn the basic knowledge about mongodb as soon as possible.

Comparison between mongodb and mysql commands

Relational databases are generally composed of three levels: database, table, and record. Instead, apsaradb for mongodb is composed of three layers: database, collection, and document. Mongodb does not have the concept of the relationship between rows and columns for tables in relational databases, which reflects the free features of the mode.

The syntax commands are shown in the following table.

MySQL	MongoDB	Description
Mysqld	Mongod	Server Daemon
Mysql	Mongo	Client Tools
Mysqldump	Mongodump	Logical backup tools
Mysql	Mongorestore	Logical recovery tool
	Db. repairDatabase ()	Restore database
Mysqldump	Mongoexport	Data export tool
Source	Export Import	Data import tool
Grant * privileges on *. *...	Db. addUser () Db. auth ()	Create a user and grant permissions
Show databases	Show dbs	Show Library List
Show tables	Show collections	Display Table list
Show slave status	Rs. status	Query master/slave status
Create table users (a int, B int)	Db. createCollection ("mycoll", {capped: true, Size: 100000}) and implicitly create a table.	Create a table
Create INDEX idxname ON users (name)	Db. users. ensureIndex ({name: 1 })	Create an index
Create INDEX idxname ON users (name, ts DESC)	Db. users. ensureIndex ({name: 1, ts:-1 })	Create an index
Insert into users values (1, 1)	Db. users. insert ({a: 1, B: 1 })	Insert record
Select a, B from users	Db. users. find ({}, {a: 1, B: 1 })	Query a table
Select * from users	Db. users. find ()	Query a table
Select * from users where age = 33	Db. users. find ({age: 33 })	Conditional query
Select a, B from users where age = 33	Db. users. find ({age: 33}, {a: 1, B: 1 })	Conditional query
Select * from users where age <33	Db. users. find ({'age': {$ lt: 33 }})	Conditional query
Select * from users where age> 33 and age <= 40	Db. users. find ({'age': {$ gt: 33, $ lte: 40 }})	Conditional query
Select * from users where a = 1 and B = 'Q'	Db. users. find ({a: 1, B: 'q '})	Conditional query
Select * from users where a = 1 or B = 2	Db. users. find ({$ or: [{a: 1 },{ B: 2}]})	Conditional query
Select * from users limit 1	Db. users. findOne ()	Conditional query
Select * from users where name like "% Joe %"	Db. users. find ({name:/Joe