what is mongo database

What is the difference between a SQL Server database and a MySQL database? A lot of friends in the IT industry. For SQL Server database and MySQL database often confuse, think these two kinds of

Tags: Need statistics Mon Select passwd count () style images classPython connection MONGO database is mainly used Pymongo connection, the general situation is divided into two kinds of connection, one through the specified port and address directly connected, and another through the format of the URI connection 1. Con

Tags: app docker node database master-slave read config Isod how to PrimaryFirst, the specific operation method1. Start two MONGO containersDocker run--name mongo1-p 21117:27017-d MONGO--noprealloc--smallfiles--replset rs1docker run--name mongo2-p 22117: 27017-d MONGO--noprealloc--smallfiles--replset rs12. Viewing a ru

Tags: io os using ar file data sp CTI onTry to use the MONGO model in thinkphp today and find out that there will always be an errorCall to a member function selectcollection () on a non-objectFor a reason, it was found that the configuration file was not imported, resulting in the inability to connect to the database and instantiate the model. Look at the configuration file, and there are no errors, the co

What is the Oracle character set? How to view the database character set? Explains how to modify the character set of oracle.1. What is the Oracle character set? The Oracle character set is a collection of symbols for the interpre

Tags: Connection successfully initialized string authorization Select Create SEL connection number1 initialization After you create the database, you can type MONGO directly (if the port is the default 27017) Use admin--Select Admin Database Db.createuser ({User: ' admin ', pwd: ' admin123 ', roles: [{role: ' Root ', d

resources, nor simply limit ourselves to the current environment. We must consider this from a scalable perspective.Task 4: manage database objects.Managing database objects is the most basic and important task of using databases. These objects include tables, indexes, views, stored procedures, functions, triggers, synonyms, and so on. To manage

I. Overview This blog is about how MONGO db imports and exports data, as well as backup data. The service side of MONGO DB needs to be opened in order to operate. Second, export. the export of MongoDB is very simple open cmd input below command

This article introduces the main causes and correct operation skills for recovering from transaction logs after the DB2 database crashes, if you are curious about the original and correct operation skills of restoring the DB2 database with transaction logs after the database crash, the following articles will unveil its secrets. Log, transaction, skill, principle

Tags: Knowledge employee DDR NET Instance hash index this related checkTurn from: 51333169 Let's start the tutorial with a simple example that explains why we need a database index. Let's say we have a database table Employee, and this table has three fields (columns), Employee_Name, Employee_age, and employee_address, respectively. Suppose the table employee has thousands of rows of data. Now suppose we wa

What is a database?This article is for the Internet to translate and modify the results:What's in the database?It is important to note that most people do not need to create their own databases. You may also not create your own ta

Original link: http://blog.163.com/baibai_zheng/blog/static/51980755201022125325689/Introduction: Recently contacted Laravel database migration, the code Schema let me to the database and the difference between the two a bit of a circle, and then have this reprint.Creating a schema in MySQL seems to have the same effect as creating a database, which looks differe

Label: Creating a schema in MySQL seems to have the same effect as creating a database, which looks different in SQL Server and Orcal databases. At the moment I can only understand that schema The relationship between user and schema in the database If we want to know what the user and schema are like in a database, w

What is the Oracle database shutdown and startup command ?, Oracle commandsPreface Log on to sqlplus with sysdba and run the following command. On windows, the background processes that constitute instances in oracle are implemented by threads derived from the oracle service, therefore, the task manager cannot see background processes such as DBWn (which can be s

Learned a period of time database, look back, incredibly also understand the principle of relational database is what, shame. First of all, learn the "cow" insights, and then slowly digest the understanding.A database is an organi

, offset 0x1 and the previous line overlap. These common errors can be solved by deleting and re-indexing. Online Index creation will read the original index to create a new index, so there will be problems with the new index. In this case, you can only delete the old one and then create a new one. In fact, this is what the CheckDB + Repair_Rebuild option does, but you must use the single-user mode when usi

What's in the database?It's worth noting that many people never need to create their own databases. You may never create your own tables or other data structures. You only need to run backup and restore and manipulate security on the system and have the application install the database for you. This is fully understandable and fully conforms to the needs of many