HS code-facilitated PL selection

List of contents of this article:

• 1,HS code-facilitated PL selectionTeach you how to quickly master the MySQL system table_MySQL< /Li>
• 2, Win10 system uses CMD command to export M ySQL table data
• 3, Interviewer: What should I do if the MySQL permission table is damaged and cannot be started?
• 4, Teach you how to set MySQL database name and table name case-sensitive in Windows and Linux systems
• 5, What are the table spaces in the database? What is the function of each table space?

Teach you how to quickly master how to upgrade the MySQL system table_MySQL

1. Before upgrading, you should back up the current M ySQL installation. Download the latest Windows version of MySQL. The server must be stopped before upgrading MySQL.

2. System internal security First, briefly introduce the directory structure of the MySQL database. MySQL is installed,After running the mysql_db_install script, the data directory and initialize the database will be established.

3. Incompatible changes: MySQL 1 supports loading or uninstalling API plug-ins at runtime without restarting the server. This feature requires the mysql.plugin table. You can run the mysql_upgrade command to create the table. The plug-in is installed in the directory referred to by the system variable plugin_dir.

How to export MySQL table data in Win10 system

1. Open [Start] [Run]After entering [cmd] and clicking [OK], the black window of the CMD command appears. This is what we call the CMD command line, as shown in the figure below: Or use the shortcut key Windows key (a key with a Windows logo on the keyboard) + R to enter cmd and return.

2. Make sure that our database has been installed correctly on the computer. First, open the command line window, open the run window with the win+R shortcut key, and enter cmd. If the mysql version is relatively new and the user name, password and port have not been modified, you can also enter the database by directly entering "mysql" in the command line.

3. First use the command mysql -uroot -p to log in to the mysql server and then execute the relevant command to import data.Mysqlusedbtest; // Set the dbtest database mysqlsetnamesutf8 of the current data to be imported; //Set the coding mysqlsourceD: db.sql; //Import data ok, complete.

Interviewer: What should I do if the MySQL permission table is damaged and cannot be started?

Due to some restrictions of docker, we will be involved twice in mysqld startup; so the way to solve this problem is to close the read_only parameter at the first start of mysqld, and turn on the read_only parameter at the second startup.

Reinstall MySQL: If none of the above methods can solve the problem, you can try to reinstall MySQL, which may be due to some file damage that causes the service to fail to start. Check the system firewall: If the system firewall blocks the start of the MySQL service, you can try to turn off the firewall or add exception rules.

Find the mysql installation directory and configure its configuration file my.Change the name of default.ini to my.ini and move my.ini to the bin directory. Start the command line and switch the directory to the bin directory of the mysql installation directory.

Confirm that MYSQL has been configured and is configured correctly. Reconfiguration. If it is a reinstalled MYSQL, please confirm that the installed MYSQL has been configured for the first time, otherwise the my.ini file will be missing. The configuration method can be selected when the installation last step, and start the configuration now. MYSQL, OR RUN THE MYSQL CONFIGURATION GURD IN THE PROGRAM GROUP.

Solution: 1) Cut out the two files of flow_data_3ibd and flow_data_3frm of the installation directory MYOAdata5TD_OA;2) Start MySQL5_OA service and import it into the TD_OA library using the backup flow_data_3sql.

Teach you how to set MySQL database name and table name case-sensitive in Windows and Linux systems

After encryption, a string is generated and stored in the table. When judging the password match, it is also based on the password entered by the user, encrypted again with the same algorithm, and then compared with the encrypted string stored in the database. So I don't think your password field needs to be case-sensitive.

Whether it is case-sensitive is related to the proofreading rules. The default rules are case-insensitive. Show create table If you see that collate ends at ci, then there is no difference. If it ends at cs or bin, it is different.

qt The steps for setting mysql case are as follows: When connecting to the MySQL database, set the connection options and turn on the case-sensitive options.When creating a table, it needs to be case-sensitive, and you need to explicitly specify the case on the table name and field name.

What are the table spaces in the database? What is the function of each table space?

1. System table space There is a file called ibdata1 under the MySQL data directory, which can save one or more tables.

2. Table space: This space is used for data storage (table, function, storage process, etc.), so it is the actual physical storage area.

3. The large file table space can be used for any of these three types of table space. The large file table space moves the maintenance point from the data file to the table space, thus simplifying the management of the table space.The large file table space contains only one data file.

4. Table space is the logical division of a database, and a table space can only belong to one database. All database objects are stored in the specified table space. But the table is mainly stored, so it is called table space. When designing the database, it is recommended that the database administrator set the table space in the following order.

5. The role of Oracle table space The role of table space can help DBA users complete the following tasks: determine the space allocation of database entities; set the space share of database users; control the availability of some data in the database; distribute data between different devices to Improve performance; backup and restore data.

6. Temporary table space is used to perform some operationsAnd index creation, etc., most of them will be automatically cleaned up after use, while the table space is the permanent space for the physical storage of normal data. The two have different purposes, and they are created separately for better management.