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MySQL SHOW Statements: Syntax, Examples, and Tips



The SHOW TRIGGERS statement shows all the triggers defined in the working database. Adding particular options allows showing trigger information from a database without selecting the database. In addition, further options allow filtering the output for refined searches.




MySQL SHOW



The Timing parameter links to the Event, indicating whether a trigger activates BEFORE or AFTER an event statement. To show triggers based on timing without connecting to a database, use the following syntax:


Note: Your user account must be granted the administration privilege for the MySQL PROCESS server to see all the threads running on an instance of MySQL. Otherwise, SHOW PROCESSLIST shows only the threads associated that are with the MySQL account that you're using. Also note that SHOW FULL PROCESSLIST and INFORMATION_SCHEMA.PROCESSLIST statements can negatively affect performance because they require a mutex.


1. Open the Command Prompt and navigate to the bin folder of your MySQL Server installation directory. Then connect to the server using the mysql -u root -p command. Enter the password and execute the SHOW DATABASES; command we have discussed above.


The index of the current master log file. For example, if the current file is named mysql-bin-changelog.012345, then the index is 12345. To determine the current master log file name, run the SHOW REPLICA STATUS command and view the Master_Log_File field.


Call mysql.rds_next_master_log only if replication fails after a failover of a Multi-AZ DB instance that is the replication source, and the Last_IO_Errno field of SHOW REPLICA STATUS reports I/O error 1236.


Calling mysql.rds_next_master_log may result in data loss in the read replica if transactions in the source instance were not written to the binary log on disk before the failover event occurred. You can reduce the chance of this happening by configuring the source instance parameters sync_binlog = 1 and innodb_support_xa = 1, although this may reduce performance. For more information, see Working with read replicas.


The Last_IO_Errno field shows that the instance is receiving I/O error 1236. The Master_Log_File field shows that the file name is mysql-bin-changelog.012345, which means that the log file index is 12345. To resolve the error, you can call mysql.rds_next_master_log with the following parameter:


This means that purging binary logs in mysql has no affect. I checked the permissions of the directory and files and all belong to mysql user and group. Why can't mysql see and/or purge those binary logs?


If no database is given, a list of database names is shown. If no table is given, all matching tables in the database are shown. If no column is given, all matching columns and column types in the table are shown.


If no database is given then all matching databases are shown. If no table is given, then all matching tables in database are shown. If no column is given, then all matching columns and column types in table are shown.


In MariaDB 10.2 and later, mysqlshow is linked with MariaDB Connector/C. However, MariaDB Connector/C does not yet handle the parsing of option files for this client. That is still performed by the server option file parsing code. See MDEV-19035 for more information.


The SHOW GRANTS requires the SELECT privilege for the mysql database, except to see the privileges for the current user, so if you have such privilege you can also list the privileges granted to the other MySQL users.


Alternatively, you can choose to manage your databases without writing SQL through the use of a database manager. This allows users access to database management functions without needing to write SQL queries. This software connects to a MySQL server and provides a user interface to expose the database functions. Once connected, the UI will show all databases on the server. The look and feel vary across management tools, but the process is similar.


If the last argument contains shell or SQL wildcard characters (*, ?, %, or _), only those names that are matched by the wildcard are shown. If a database name contains any underscores, those should be escaped with a backslash (some Unix shells require two) to get a list of the proper tables or columns. * and ? characters are converted into SQL % and _ wildcard characters. This might cause some confusion when you try to display the columns for a table with a _ in the name, because in this case, mysqlshow shows you only the table names that match the pattern. This is easily fixed by adding an extra % last on the command line as a separate argument.


Read not only the usual option groups, but also groups with the usual names and a suffix of str. For example, mysqlshow normally reads the [client] and [mysqlshow] groups. If this option is given as --defaults-group-suffix=_other, mysqlshow also reads the [client_other] and [mysqlshow_other] groups.


The password of the MySQL account used for connecting to the server. The password value is optional. If not given, mysqlshow prompts for one. If given, there must be no space between --password= or -p and the password following it. If no password option is specified, the default is to send no password.


The explain plan shows the operations MySQL performs when it runs SQL statements. This information can help optimize SQL performance. MySQLWorkbench Visualize Explain plans graphically show and highlight how SQL statements execute within MySQL. By showing developers costs and tuning hints, MySQL Workbench improves and simplifies SQL statement performance tuning.


However, note that this query shows all of the columns from the mysql.user table. This makes for a lot of output, so as a practical matter you may want to trim down some of the fields to display, something like this:


In MySQL, there isn't a show users command, as most people assume. The MySQL command shows information about the database, but there are other commands you can use to see that information. SHOW DATABASES, for example, will display our MySQL Server's databases, while SHOW TABLES will display the tables in the MySQL database you selected.


Then enter your MySQL root password. It is not set by default, so all you need to do is press the [Enter] key if you never set it. However, if you have set the password (whether with the mysql_secure_installation script or something else), you should enter that password now.


If you have any additional questions on the MySQL database, feel free to leave a comment below. You can always get a Managed MySQL hosting from us and our fully managed support will help you with problems related to MySQL or will explain how to show all users in the MySQL database.


Then try accessing the MySQL prompt again. If you still receive the socket error, double check the location where your MySQL installation is looking for the socket file. This information can be found in the mysqld.cnf file:


Note: By default, mysqldump command does not dump the information_schema database, performance_schema, and MySQL Cluster ndbinfo database.


There are lots of options and features that can be used with mysqldump. You can view the complete list of options here. I am going to some of the basic features. Following is the syntax of the mysqldump utility.


Restoring a MySQL database using mysqldump is simple. To restore the database, you must create an empty database. First, let us drop and recreate the sakila database by executing the following command.


When you restore the database, instead of using mysqldump, you must use mysql; otherwise, the mysqldump will not generate the schema and the data. Execute the following command to restore the sakila database:


Note that three keys have been added to the configuration array: read, write and sticky. The read and write keys have array values containing a single key: host. The rest of the database options for the read and write connections will be merged from the main mysql configuration array.


You only need to place items in the read and write arrays if you wish to override the values from the main mysql array. So, in this case, 192.168.1.1 will be used as the host for the "read" connection, while 192.168.1.3 will be used for the "write" connection. The database credentials, prefix, character set, and all other options in the main mysql array will be shared across both connections. When multiple values exist in the host configuration array, a database host will be randomly chosen for each request.


Using the db:show and db:table Artisan commands, you can get valuable insight into your database and its associated tables. To see an overview of your database, including its size, type, number of open connections, and a summary of its tables, you may use the db:show command: 2ff7e9595c


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