There are many different programs in a MySQL installation. This section provides a brief overview of them. Later sections provide a more detailed description of each one, with the exception of NDB Cluster programs. Each program's description indicates its invocation syntax and the options that it supports. Section 23.5, “NDB Cluster Programs”, describes programs specific to NDB Cluster.
Most MySQL distributions include all of these programs, except for those programs that are platform-specific. (For example, the server startup scripts are not used on Windows.) The exception is that RPM distributions are more specialized. There is one RPM for the server, another for client programs, and so forth. If you appear to be missing one or more programs, see Chapter 2, Installing and Upgrading MySQL, for information on types of distributions and what they contain. It may be that you have a distribution that does not include all programs and you need to install an additional package.
Each MySQL program takes many different options. Most programs
--help option that you can use to get a
description of the program's different options. For example, try
You can override default option values for MySQL programs by specifying options on the command line or in an option file. See Section 4.2, “Using MySQL Programs”, for general information on invoking programs and specifying program options.
The MySQL server, mysqld, is the main program that does most of the work in a MySQL installation. The server is accompanied by several related scripts that assist you in starting and stopping the server:
The SQL daemon (that is, the MySQL server). To use client programs, mysqld must be running, because clients gain access to databases by connecting to the server. See Section 4.3.1, “mysqld — The MySQL Server”.
A server startup script. mysqld_safe attempts to start mysqld. See Section 4.3.2, “mysqld_safe — MySQL Server Startup Script”.
A server startup script. This script is used on systems that use System V-style run directories containing scripts that start system services for particular run levels. It invokes mysqld_safe to start the MySQL server. See Section 4.3.3, “mysql.server — MySQL Server Startup Script”.
A server startup script that can start or stop multiple servers installed on the system. See Section 4.3.4, “mysqld_multi — Manage Multiple MySQL Servers”.
Several programs perform setup operations during MySQL installation or upgrading:
This program is used during the MySQL build/installation process. It compiles error message files from the error source files. See Section 4.4.1, “comp_err — Compile MySQL Error Message File”.
This program enables you to improve the security of your MySQL installation. See Section 4.4.2, “mysql_secure_installation — Improve MySQL Installation Security”.
mysql_ssl_rsa_setup is deprecated as of MySQL 8.0.34.
This program creates the SSL certificate and key files and RSA key-pair files required to support secure connections, if those files are missing. Files created by mysql_ssl_rsa_setup can be used for secure connections using SSL or RSA. See Section 4.4.3, “mysql_ssl_rsa_setup — Create SSL/RSA Files”.
This program loads the time zone tables in the
mysqldatabase using the contents of the host system zoneinfo database (the set of files describing time zones). See Section 4.4.4, “mysql_tzinfo_to_sql — Load the Time Zone Tables”.
Prior to MySQL 8.0.16, this program is used after a MySQL upgrade operation. It updates the grant tables with any changes that have been made in newer versions of MySQL, and checks tables for incompatibilities and repairs them if necessary. See Section 4.4.5, “mysql_upgrade — Check and Upgrade MySQL Tables”.
As of MySQL 8.0.16, the MySQL server performs the upgrade tasks previously handled by mysql_upgrade (for details, see Section 2.10.3, “What the MySQL Upgrade Process Upgrades”).
MySQL client programs that connect to the MySQL server:
The command-line tool for interactively entering SQL statements or executing them from a file in batch mode. See Section 4.5.1, “mysql — The MySQL Command-Line Client”.
A client that performs administrative operations, such as creating or dropping databases, reloading the grant tables, flushing tables to disk, and reopening log files. mysqladmin can also be used to retrieve version, process, and status information from the server. See Section 4.5.2, “mysqladmin — A MySQL Server Administration Program”.
A table-maintenance client that checks, repairs, analyzes, and optimizes tables. See Section 4.5.3, “mysqlcheck — A Table Maintenance Program”.
A client that dumps a MySQL database into a file as SQL, text, or XML. See Section 4.5.4, “mysqldump — A Database Backup Program”.
A client that imports text files into their respective tables using
LOAD DATA. See Section 4.5.5, “mysqlimport — A Data Import Program”.
A client that dumps a MySQL database into a file as SQL. See Section 4.5.6, “mysqlpump — A Database Backup Program”.
A client that displays information about databases, tables, columns, and indexes. See Section 4.5.7, “mysqlshow — Display Database, Table, and Column Information”.
A client that is designed to emulate client load for a MySQL server and report the timing of each stage. It works as if multiple clients are accessing the server. See Section 4.5.8, “mysqlslap — A Load Emulation Client”.
MySQL administrative and utility programs:
InnoDBoffline file checksum utility. See Section 4.6.2, “innochecksum — Offline InnoDB File Checksum Utility”.
A utility that displays information about full-text indexes in
MyISAMtables. See Section 4.6.3, “myisam_ftdump — Display Full-Text Index information”.
A utility to describe, check, optimize, and repair
MyISAMtables. See Section 4.6.4, “myisamchk — MyISAM Table-Maintenance Utility”.
A utility that processes the contents of a
MyISAMlog file. See Section 4.6.5, “myisamlog — Display MyISAM Log File Contents”.
A utility that compresses
MyISAMtables to produce smaller read-only tables. See Section 4.6.6, “myisampack — Generate Compressed, Read-Only MyISAM Tables”.
A utility that enables you to store authentication credentials in a secure, encrypted login path file named
.mylogin.cnf. See Section 4.6.7, “mysql_config_editor — MySQL Configuration Utility”.
A utility for migrating keys between one keyring component and another. See Section 4.6.8, “mysql_migrate_keyring — Keyring Key Migration Utility”.
A utility for reading statements from a binary log. The log of executed statements contained in the binary log files can be used to help recover from a crash. See Section 4.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”.
A utility to read and summarize the contents of a slow query log. See Section 4.6.10, “mysqldumpslow — Summarize Slow Query Log Files”.
MySQL program-development utilities:
A shell script that produces the option values needed when compiling MySQL programs. See Section 4.7.1, “mysql_config — Display Options for Compiling Clients”.
A utility that shows which options are present in option groups of option files. See Section 4.7.2, “my_print_defaults — Display Options from Option Files”.
A utility that decompresses mysqlpump output that was created using LZ4 compression. See Section 4.8.1, “lz4_decompress — Decompress mysqlpump LZ4-Compressed Output”.
A utility that displays the meaning of system or MySQL error codes. See Section 4.8.2, “perror — Display MySQL Error Message Information”.
A utility that decompresses mysqlpump output that was created using ZLIB compression. See Section 4.8.3, “zlib_decompress — Decompress mysqlpump ZLIB-Compressed Output”.
Oracle Corporation also provides the MySQL Workbench GUI tool, which is used to administer MySQL servers and databases, to create, execute, and evaluate queries, and to migrate schemas and data from other relational database management systems for use with MySQL.
MySQL client programs that communicate with the server using the MySQL client/server library use the following environment variables.
||The default Unix socket file; used for connections to
||The default port number; used for TCP/IP connections|
||Debug trace options when debugging|
||The directory where temporary tables and files are created|
For a full list of environment variables used by MySQL programs, see Section 4.9, “Environment Variables”.