xml online formatting

The article introduces the operation of MySQL database. First, you need to install a MySQL client, such as MySQLWorkbench or command line client. 1. Use the mysql-uroot-p command to connect to the server and log in with the root account password; 2. Use CREATEDATABASE to create a database, and USE select a database; 3. Use CREATETABLE to create a table, define fields and data types; 4. Use INSERTINTO to insert data, query data, update data by UPDATE, and delete data by DELETE. Only by mastering these steps, learning to deal with common problems and optimizing database performance can you use MySQL efficiently.

The main reasons why you cannot log in to MySQL as root are permission problems, configuration file errors, password inconsistent, socket file problems, or firewall interception. The solution includes: check whether the bind-address parameter in the configuration file is configured correctly. Check whether the root user permissions have been modified or deleted and reset. Verify that the password is accurate, including case and special characters. Check socket file permission settings and paths. Check that the firewall blocks connections to the MySQL server.

Bootstrap Table garbled is usually because the page encoding is inconsistent with the table data encoding. To solve this problem, you need to make sure they are consistent. The specific steps include: checking page and table data encoding, setting page encoding, and verifying the encoding. If UTF-8 is used, the server should also support it. If it cannot be resolved, try using the JavaScript encoding library.

MySQL cannot run directly on Android, but it can be implemented indirectly by using the following methods: using the lightweight database SQLite, which is built on the Android system, does not require a separate server, and has a small resource usage, which is very suitable for mobile device applications. Remotely connect to the MySQL server and connect to the MySQL database on the remote server through the network for data reading and writing, but there are disadvantages such as strong network dependencies, security issues and server costs.

Navicat for MariaDB cannot view the database password directly because the password is stored in encrypted form. To ensure the database security, there are three ways to reset your password: reset your password through Navicat and set a complex password. View the configuration file (not recommended, high risk). Use system command line tools (not recommended, you need to be proficient in command line tools).

There is no absolutely optimal MySQL database backup and recovery solution, and it needs to be selected based on the amount of data, business importance, RTO and RPO. 1. Logical backup (mysqldump) is simple and easy to use, suitable for small databases, but slow and huge files; 2. Physical backup (xtrabackup) is fast, suitable for large databases, but is more complicated to use. The backup strategy needs to consider the backup frequency (RPO decision), backup method (data quantity and time requirement decision) and storage location (off-site storage is more secure), and regularly test the backup and recovery process to avoid backup file corruption, permission problems, insufficient storage space, network interruption and untested issues, and ensure data security.

It is impossible to view PostgreSQL passwords directly from Navicat, because Navicat stores passwords encrypted for security reasons. To confirm the password, try to connect to the database; to modify the password, please use the graphical interface of psql or Navicat; for other purposes, you need to configure connection parameters in the code to avoid hard-coded passwords. To enhance security, it is recommended to use strong passwords, periodic modifications and enable multi-factor authentication.

Recovering deleted rows directly from the database is usually impossible unless there is a backup or transaction rollback mechanism. Key point: Transaction rollback: Execute ROLLBACK before the transaction is committed to recover data. Backup: Regular backup of the database can be used to quickly restore data. Database snapshot: You can create a read-only copy of the database and restore the data after the data is deleted accidentally. Use DELETE statement with caution: Check the conditions carefully to avoid accidentally deleting data. Use the WHERE clause: explicitly specify the data to be deleted. Use the test environment: Test before performing a DELETE operation.