neulab/tldr huggingface dataset:
Devices can be globally identified via their unique identifier (uuid). All commands that take a DEVICE identifier expect this unique id.
If no command is given, it is equivalent to boltctl list.
-U | --uuid {full | short | alias | N} Control how UUIDs are printed. Since they are somewhat sensitive data it is not advisable to share them publicly in full length. Instead short or alias can and should be used when sharing the output of boltctl.
full Print all UUIDs in full length.
short Truncate all UUIDs so only the first 13 characters are printed.
alias All UUIDs are replaced by a random string that is derived from the UUID, therefore the devices can be uniquely identified without revealing the original UUID.
N If a integer N is specified, all UUIDs are truncated to only show up to N.
authorize [-F | --first-time] DEVICE Authorize a currently unauthorized device identified via its unique id (uuid) DEVICE. If a key is stored in the database it will be used, given the security level of the domain supports secure device connection. Use boltctl list to find out the uuid of a device.
-F | --first-time Normally, when attempting to authorize an already authorized device boltctl will do nothing and return a successful status code. When using this option, the attempt will fail and result in a negative exit code if the device is already authorized.
config --describe [global|domain|device] List global, domain, or all (if nothing is specified) properties. The format is 3 columns: permission, name, description. Permission indicates if the property is only readable or can also be written.
config KEY [VALUE] Get or set, if VALUE is specified, a global property.
config <domain|device>.KEY TARGET [VALUE] Get or set, if VALUE is specified, a domain or device property, where TARGET is the unique id of the domain or the device.
domains [-v | --verbose] List all currently active Thunderbolt domains. A Thunderbolt domain represents the Thunderbolt controller hardware. There will be one domain (and host device) for each Thunderbolt controller present in the system. The security property shows the security level of the controller. If iommu support is active (see the boltd man page) it will be indicated by a +iommu suffix for "secure" or "user" mode, or just plain iommu in case the security level is "none" (sl0). bootacl shows the used and total slots of the boot access control list (BootACL) and the content of all non-empty entries. NB: if BootACL is unsupported it will show 0 for both (0/0). The online property shows if the thunderbolt controller is currently powered by the firmware. NB: if the controller is currently offline the BootACL list will reflect what boltd estimates the list will look like once the controller is back online and local changes have been synchronized to the controller. This might not be accurate if the list was modified in the meantime, e.g. from a different installation or OS.
enroll [--policy policy] DEVICE Authorize and record the device with the unique id DEVICE in the database. If the domain supports secure connection a new key will be generated and stored in the database alongside the device name and vendor name. The key, if created, will be used in the future to securely authorize the device.
--policy {default | auto | manual} Specify the policy to be used for the newly enrolled device.
default Use the global default policy of the daemon; this can be changed, but is normally also auto.
auto Automatically authorize this device whenever it is connected.
manual Do not automatically authorize the device; instead require manual authorization via boltctl authorize.
forget DEVICE Remove the information about the device with the unique id DEVICE from the database. This includes the key, if one was previously generated. If you pass --all instead of the DEVICE all devices are removed instead of just one.
info DEVICE Display information about the device with the unique id DEVICE.
list [-a | --all] List and print information about all connected and stored devices.
-a | --all Normally, the only the device type that will be shown is peripherals. Therefore the device that represents the host itself will be omitted. Using this option will instead include all device types in the list.
monitor Listen for and show changes in connected devices.
power [-t | --timeout seconds] [-q | --query] Power up the Thunderbolt controller. If the Thunderbolt controller is not in "native enumeration mode" it can be completely powered down by the host firmware/BIOS. On supported systems there is an interface to "force" power the thunderbolt controller. If supported this command will request the daemon to do so. The daemon will keep track of all client requests and will release the force power override when the last request is released.
-t | --timeout seconds Release the force power request after the specified amount of seconds and exit.
-q | --query Query the current force power status of the daemon.
Written by Christian Kellner <ckellner@redhat.com>.
MYSQL(1)                      MySQL Database System                     MYSQL(1)
mysql - the MySQL command-line client
mysql [options] db_name
mysql is a simple SQL shell with input line editing capabilities. It supports interactive and noninteractive use. When used interactively, query results are presented in an ASCII-table format. When used noninteractively (for example, as a filter), the result is presented in tab-separated format. The output format can be changed using command options.
If you have problems due to insufficient memory for large result sets, use the --quick option. This forces mysql to retrieve results from the server a row at a time rather than retrieving the entire result set and buffering it in memory before displaying it. This is done by returning the result set using the mysql_use_result() C API function in the client/server library rather than mysql_store_result().
Note Alternatively, MySQL Shell offers access to the X DevAPI. For details, see MySQL Shell 8.0[1].
Using mysql is very easy. Invoke it from the prompt of your command interpreter as follows:
mysql db_name
mysql --user=user_name --password db_name
In this case, you'll need to enter your password in response to the prompt that mysql displays:
Enter password: your_password
Then type an SQL statement, end it with ;, \g, or \G and press Enter.
Typing Control+C interrupts the current statement if there is one, or cancels any partial input line otherwise.
You can execute SQL statements in a script file (batch file) like this:
mysql db_name < script.sql > output.tab
On Unix, the mysql client logs statements executed interactively to a history file. See the section called “MYSQL CLIENT LOGGING”.
mysql supports the following options, which can be specified on the command line or in the [mysql] and [client] groups of an option file. For information about option files used by MySQL programs, see Section 4.2.2.2, “Using Option Files”.
•   --auto-rehash Enable automatic rehashing. This option is on by default, which enables database, table, and column name completion. Use --disable-auto-rehash to disable rehashing. That causes mysql to start faster, but you must issue the rehash command or its \# shortcut if you want to use name completion.
To complete a name, enter the first part and press Tab. If the name is unambiguous, mysql completes it. Otherwise, you can press Tab again to see the possible names that begin with what you have typed so far. Completion does not occur if there is no default database.
Note This feature requires a MySQL client that is compiled with the readline library. Typically, the readline library is not available on Windows.
•   --auto-vertical-output Cause result sets to be displayed vertically if they are too wide for the current window, and using normal tabular format otherwise. (This applies to statements terminated by ; or \G.)
•   --batch, -B Print results using tab as the column separator, with each row on a new line. With this option, mysql does not use the history file.
Batch mode results in nontabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the --raw option.
•   --binary-as-hex When this option is given, mysql displays binary data using hexadecimal notation (0xvalue). This occurs whether the overall output display format is tabular, vertical, HTML, or XML.
--binary-as-hex when enabled affects display of all binary strings, including those returned by functions such as CHAR() and UNHEX(). The following example demonistrates this using the ASCII code for A (65 decimal, 41 hexadecimal):
•   --binary-as-hex disabled:
mysql> SELECT CHAR(0x41), UNHEX('41'); +------------+-------------+ | CHAR(0x41) | UNHEX('41') | +------------+-------------+ | A          | A           | +------------+-------------+
•   --binary-as-hex enabled:
mysql> SELECT CHAR(0x41), UNHEX('41'); +------------------------+--------------------------+ | CHAR(0x41)             | UNHEX('41')              | +------------------------+--------------------------+ | 0x41                   | 0x41                     | +------------------------+--------------------------+
To write a binary string expression so that it displays as a character string regardless of whether --binary-as-hex is enabled, use these techniques:
•   The CHAR() function has a USING charset clause:
mysql> SELECT CHAR(0x41 USING utf8mb4); +--------------------------+ | CHAR(0x41 USING utf8mb4) | +--------------------------+ | A                        | +--------------------------+
•   More generally, use CONVERT() to convert an expression to a given character set:
mysql> SELECT CONVERT(UNHEX('41') USING utf8mb4); +------------------------------------+ | CONVERT(UNHEX('41') USING utf8mb4) | +------------------------------------+ | A                                  | +------------------------------------+
As of MySQL 8.0.19, when mysql operates in interactive mode, this option is enabled by default. In addition, output from the status (or \s) command includes this line when the option is enabled implicitly or explicitly:
Binary data as: Hexadecimal
To disable hexadecimal notation, use --skip-binary-as-hex
•   --binary-mode This option helps when processing mysqlbinlog output that may contain BLOB values. By default, mysql translates \r\n in statement strings to \n and interprets \0 as the statement terminator.  --binary-mode disables both features. It also disables all mysql commands except charset and delimiter in noninteractive mode (for input piped to mysql or loaded using the source command).
•   --column-names Write column names in results.
•   --column-type-info Display result set metadata. This information corresponds to the contents of C API MYSQL_FIELD data structures. See C API Basic Data Structures[2].
•   --comments, -c Whether to strip or preserve comments in statements sent to the server. The default is --skip-comments (strip comments), enable with --comments (preserve comments).
Note The mysql client always passes optimizer hints to the server, regardless of whether this option is given.
Comment stripping is deprecated. Expect this feature and the options to control it to be removed in a future MySQL release.
As of MySQL 8.0.18, this option is deprecated. Expect it be removed in a future version of MySQL. See the section called “Configuring Legacy Connection Compression”.
•   --connect-expired-password Indicate to the server that the client can handle sandbox mode if the account used to connect has an expired password. This can be useful for noninteractive invocations of mysql because normally the server disconnects noninteractive clients that attempt to connect using an account with an expired password. (See Section 6.2.16, “Server Handling of Expired Passwords”.)
•   --connect-timeout=value The number of seconds before connection timeout. (Default value is 0.)
•   --database=db_name, -D db_name The database to use. This is useful primarily in an option file.
•   --debug[=debug_options], -# [debug_options] Write a debugging log. A typical debug_options string is d:t:o,file_name. The default is d:t:o,/tmp/mysql.trace.
•   --debug-info, -T Print debugging information and memory and CPU usage statistics when the program exits.
•   --default-character-set=charset_name Use charset_name as the default character set for the client and connection.
This option can be useful if the operating system uses one character set and the mysql client by default uses another. In this case, output may be formatted incorrectly. You can usually fix such issues by using this option to force the client to use the system character set instead.
For more information, see Section 10.4, “Connection Character Sets and Collations”, and Section 10.15, “Character Set Configuration”.
•   --defaults-group-suffix=str Read not only the usual option groups, but also groups with the usual names and a suffix of str. For example, mysql normally reads the [client] and [mysql] groups. If this option is given as --defaults-group-suffix=_other, mysql also reads the [client_other] and [mysql_other] groups.
•   --delimiter=str Set the statement delimiter. The default is the semicolon character (;).
•   --disable-named-commands Disable named commands. Use the \* form only, or use named commands only at the beginning of a line ending with a semicolon (;).  mysql starts with this option enabled by default. However, even with this option, long-format commands still work from the first line. See the section called “MYSQL CLIENT COMMANDS”.
•   --dns-srv-name=name Specifies the name of a DNS SRV record that determines the candidate hosts to use for establishing a connection to a MySQL server. For information about DNS SRV support in MySQL, see Section 4.2.6, “Connecting to the Server Using DNS SRV Records”.
Suppose that DNS is configured with this SRV information for the example.com domain:
Name                     TTL   Class   Priority Weight Port Target _mysql._tcp.example.com. 86400 IN SRV  0        5      3306 host1.example.com _mysql._tcp.example.com. 86400 IN SRV  0        10     3306 host2.example.com _mysql._tcp.example.com. 86400 IN SRV  10       5      3306 host3.example.com _mysql._tcp.example.com. 86400 IN SRV  20       5      3306 host4.example.com
To use that DNS SRV record, invoke mysql like this:
mysql --dns-srv-name=_mysql._tcp.example.com
mysql then attempts a connection to each server in the group until a successful connection is established. A failure to connect occurs only if a connection cannot be established to any of the servers. The priority and weight values in the DNS SRV record determine the order in which servers should be tried.
When invoked with --dns-srv-name, mysql attempts to establish TCP connections only.
The --dns-srv-name option takes precedence over the --host option if both are given.  --dns-srv-name causes connection establishment to use the mysql_real_connect_dns_srv() C API function rather than mysql_real_connect(). However, if the connect command is subsequently used at runtime and specifies a host name argument, that host name takes precedence over any --dns-srv-name option given at mysql startup to specify a DNS SRV record.
This option was added in MySQL 8.0.22.
•   --execute=statement, -e statement Execute the statement and quit. The default output format is like that produced with --batch. See Section 4.2.2.1, “Using Options on the Command Line”, for some examples. With this option, mysql does not use the history file.
•   --force, -f Continue even if an SQL error occurs.
•   --histignore A list of one or more colon-separated patterns specifying statements to ignore for logging purposes. These patterns are added to the default pattern list ("*IDENTIFIED*:*PASSWORD*"). The value specified for this option affects logging of statements written to the history file, and to syslog if the --syslog option is given. For more information, see the section called “MYSQL CLIENT LOGGING”.
•   --host=host_name, -h host_name Connect to the MySQL server on the given host.
•   --html, -H Produce HTML output.
•   --ignore-spaces, -i Ignore spaces after function names. The effect of this is described in the discussion for the IGNORE_SPACE SQL mode (see Section 5.1.11, “Server SQL Modes”).
•   --init-command=str SQL statement to execute after connecting to the server. If auto-reconnect is enabled, the statement is executed again after reconnection occurs.
•   --line-numbers Write line numbers for errors. Disable this with --skip-line-numbers.
•   --load-data-local-dir=dir_name This option affects the client-side LOCAL capability for LOAD DATA operations. It specifies the directory in which files named in LOAD DATA LOCAL statements must be located. The effect of --load-data-local-dir depends on whether LOCAL data loading is enabled or disabled:
•   If LOCAL data loading is enabled, either by default in the MySQL client library or by specifying --local-infile[=1], the --load-data-local-dir option is ignored.
•   If LOCAL data loading is disabled, either by default in the MySQL client library or by specifying --local-infile=0, the --load-data-local-dir option applies.
When --load-data-local-dir applies, the option value designates the directory in which local data files must be located. Comparison of the directory path name and the path name of files to be loaded is case-sensitive regardless of the case sensitivity of the underlying file system. If the option value is the empty string, it names no directory, with the result that no files are permitted for local data loading.
For example, to explicitly disable local data loading except for files located in the /my/local/data directory, invoke mysql like this:
mysql --local-infile=0 --load-data-local-dir=/my/local/data
When both --local-infile and --load-data-local-dir are given, the order in which they are given does not matter.
Successful use of LOCAL load operations within mysql also requires that the server permits local loading; see Section 6.1.6, “Security Considerations for LOAD DATA LOCAL”
The --load-data-local-dir option was added in MySQL 8.0.21.
•   --local-infile[={0|1}] By default, LOCAL capability for LOAD DATA is determined by the default compiled into the MySQL client library. To enable or disable LOCAL data loading explicitly, use the --local-infile option. When given with no value, the option enables LOCAL data loading. When given as --local-infile=0 or --local-infile=1, the option disables or enables LOCAL data loading.
If LOCAL capability is disabled, the --load-data-local-dir option can be used to permit restricted local loading of files located in a designated directory.
•   --max-allowed-packet=value The maximum size of the buffer for client/server communication. The default is 16MB, the maximum is 1GB.
•   --max-join-size=value The automatic limit for rows in a join when using --safe-updates. (Default value is 1,000,000.)
•   --named-commands, -G Enable named mysql commands. Long-format commands are permitted, not just short-format commands. For example, quit and \q both are recognized. Use --skip-named-commands to disable named commands. See the section called “MYSQL CLIENT COMMANDS”.
•   --net-buffer-length=value The buffer size for TCP/IP and socket communication. (Default value is 16KB.)
•   --network-namespace=name The network namespace to use for TCP/IP connections. If omitted, the connection uses the default (global) namespace. For information about network namespaces, see Section 5.1.14, “Network Namespace Support”.
This option was added in MySQL 8.0.22. It is available only on platforms that implement network namespace support.
•   --no-auto-rehash, -A This has the same effect as --skip-auto-rehash. See the description for --auto-rehash.
•   --no-beep, -b Do not beep when errors occur.
•   --one-database, -o Ignore statements except those that occur while the default database is the one named on the command line. This option is rudimentary and should be used with care. Statement filtering is based only on USE statements.
Initially, mysql executes statements in the input because specifying a database db_name on the command line is equivalent to inserting USE db_name at the beginning of the input. Then, for each USE statement encountered, mysql accepts or rejects following statements depending on whether the database named is the one on the command line. The content of the statements is immaterial.
Suppose that mysql is invoked to process this set of statements:
DELETE FROM db2.t2; USE db2; DROP TABLE db1.t1; CREATE TABLE db1.t1 (i INT); USE db1; INSERT INTO t1 (i) VALUES(1); CREATE TABLE db2.t1 (j INT);
If the command line is mysql --force --one-database db1, mysql handles the input as follows:
•   The DELETE statement is executed because the default database is db1, even though the statement names a table in a different database.
•   The DROP TABLE and CREATE TABLE statements are not executed because the default database is not db1, even though the statements name a table in db1.
•   The INSERT and CREATE TABLE statements are executed because the default database is db1, even though the CREATE TABLE statement names a table in a different database.
•   --pager[=command] Use the given command for paging query output. If the command is omitted, the default pager is the value of your PAGER environment variable. Valid pagers are less, more, cat [> filename], and so forth. This option works only on Unix and only in interactive mode. To disable paging, use --skip-pager.  the section called “MYSQL CLIENT COMMANDS”, discusses output paging further.
•   --password[=password], -p[password] The password of the MySQL account used for connecting to the server. The password value is optional. If not given, mysql 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.
To explicitly specify that there is no password and that mysql should not prompt for one, use the --skip-password option.
•   --plugin-dir=dir_name The directory in which to look for plugins. Specify this option if the --default-auth option is used to specify an authentication plugin but mysql does not find it. See Section 6.2.17, “Pluggable Authentication”.
•   --prompt=format_str Set the prompt to the specified format. The default is mysql>. The special sequences that the prompt can contain are described in the section called “MYSQL CLIENT COMMANDS”.
•   --quick, -q Do not cache each query result, print each row as it is received. This may slow down the server if the output is suspended. With this option, mysql does not use the history file.
•   --raw, -r For tabular output, the “boxing” around columns enables one column value to be distinguished from another. For nontabular output (such as is produced in batch mode or when the --batch or --silent option is given), special characters are escaped in the output so they can be identified easily. Newline, tab, NUL, and backslash are written as \n, \t, \0, and \\. The --raw option disables this character escaping.
The following example demonstrates tabular versus nontabular output and the use of raw mode to disable escaping:
% mysql mysql> SELECT CHAR(92); +----------+ | CHAR(92) | +----------+ | \        | +----------+ % mysql -s mysql> SELECT CHAR(92); CHAR(92) \\ % mysql -s -r mysql> SELECT CHAR(92); CHAR(92) \
•   --reconnect If the connection to the server is lost, automatically try to reconnect. A single reconnect attempt is made each time the connection is lost. To suppress reconnection behavior, use --skip-reconnect.
•   --safe-updates, --i-am-a-dummy, -U If this option is enabled, UPDATE and DELETE statements that do not use a key in the WHERE clause or a LIMIT clause produce an error. In addition, restrictions are placed on SELECT statements that produce (or are estimated to produce) very large result sets. If you have set this option in an option file, you can use --skip-safe-updates on the command line to override it. For more information about this option, see Using Safe-Updates Mode (--safe-updates).
•   --select-limit=value The automatic limit for SELECT statements when using --safe-updates. (Default value is 1,000.)
•   --show-warnings Cause warnings to be shown after each statement if there are any. This option applies to interactive and batch mode.
•   --sigint-ignore Ignore SIGINT signals (typically the result of typing Control+C).
Without this option, typing Control+C interrupts the current statement if there is one, or cancels any partial input line otherwise.
•   --silent, -s Silent mode. Produce less output. This option can be given multiple times to produce less and less output.
This option results in nontabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the --raw option.
•   --skip-column-names, -N Do not write column names in results.
•   --skip-line-numbers, -L Do not write line numbers for errors. Useful when you want to compare result files that include error messages.
•   --syslog, -j This option causes mysql to send interactive statements to the system logging facility. On Unix, this is syslog; on Windows, it is the Windows Event Log. The destination where logged messages appear is system dependent. On Linux, the destination is often the /var/log/messages file.
Here is a sample of output generated on Linux by using --syslog. This output is formatted for readability; each logged message actually takes a single line.
Mar  7 12:39:25 myhost MysqlClient[20824]: SYSTEM_USER:'oscar', MYSQL_USER:'my_oscar', CONNECTION_ID:23, DB_SERVER:'127.0.0.1', DB:'--', QUERY:'USE test;' Mar  7 12:39:28 myhost MysqlClient[20824]: SYSTEM_USER:'oscar', MYSQL_USER:'my_oscar', CONNECTION_ID:23, DB_SERVER:'127.0.0.1', DB:'test', QUERY:'SHOW TABLES;'
For more information, see the section called “MYSQL CLIENT LOGGING”.
•   --table, -t Display output in table format. This is the default for interactive use, but can be used to produce table output in batch mode.
•   --tee=file_name Append a copy of output to the given file. This option works only in interactive mode.  the section called “MYSQL CLIENT COMMANDS”, discusses tee files further.
•   --unbuffered, -n Flush the buffer after each query.
•   --verbose, -v Verbose mode. Produce more output about what the program does. This option can be given multiple times to produce more and more output. (For example, -v -v -v produces table output format even in batch mode.)
•   --version, -V Display version information and exit.
•   --vertical, -E Print query output rows vertically (one line per column value). Without this option, you can specify vertical output for individual statements by terminating them with \G.
•   --wait, -w If the connection cannot be established, wait and retry instead of aborting.
•   --xml, -X Produce XML output.
<field name="column_name">NULL</field>
The output when --xml is used with mysql matches that of mysqldump --xml. See mysqldump(1), for details.
The XML output also uses an XML namespace, as shown here:
shell> mysql --xml -uroot -e "SHOW VARIABLES LIKE 'version%'" <?xml version="1.0"?> <resultset statement="SHOW VARIABLES LIKE 'version%'" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <row> <field name="Variable_name">version</field> <field name="Value">5.0.40-debug</field> </row> <row> <field name="Variable_name">version_comment</field> <field name="Value">Source distribution</field> </row> <row> <field name="Variable_name">version_compile_machine</field> <field name="Value">i686</field> </row> <row> <field name="Variable_name">version_compile_os</field> <field name="Value">suse-linux-gnu</field> </row> </resultset>
mysql sends each SQL statement that you issue to the server to be executed. There is also a set of commands that mysql itself interprets. For a list of these commands, type help or \h at the mysql> prompt:
mysql> help List of all MySQL commands: Note that all text commands must be first on line and end with ';' ?         (\?) Synonym for `help'. clear     (\c) Clear the current input statement. connect   (\r) Reconnect to the server. Optional arguments are db and host. delimiter (\d) Set statement delimiter. edit      (\e) Edit command with $EDITOR. ego       (\G) Send command to mysql server, display result vertically. exit      (\q) Exit mysql. Same as quit. go        (\g) Send command to mysql server. help      (\h) Display this help. nopager   (\n) Disable pager, print to stdout. notee     (\t) Don't write into outfile. pager     (\P) Set PAGER [to_pager]. Print the query results via PAGER. print     (\p) Print current command. prompt    (\R) Change your mysql prompt. quit      (\q) Quit mysql. rehash    (\#) Rebuild completion hash. source    (\.) Execute an SQL script file. Takes a file name as an argument. status    (\s) Get status information from the server. system    (\!) Execute a system shell command. tee       (\T) Set outfile [to_outfile]. Append everything into given outfile. use       (\u) Use another database. Takes database name as argument. charset   (\C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets. warnings  (\W) Show warnings after every statement. nowarning (\w) Don't show warnings after every statement. resetconnection(\x) Clean session context. query_attributes(\) Sets string parameters (name1 value1 name2 value2 ...) for the next query to pick up. For server side help, type 'help contents'
If mysql is invoked with the --binary-mode option, all mysql commands are disabled except charset and delimiter in noninteractive mode (for input piped to mysql or loaded using the source command).
Each command has both a long and short form. The long form is not case-sensitive; the short form is. The long form can be followed by an optional semicolon terminator, but the short form should not.
The use of short-form commands within multiple-line /* ... */ comments is not supported. Short-form commands do work within single-line /*! ... */ version comments, as do /*+ ... */ optimizer-hint comments, which are stored in object definitions. If there is a concern that optimizer-hint comments may be stored in object definitions so that dump files when reloaded with mysql would result in execution of such commands, either invoke mysql with the --binary-mode option or use a reload client other than mysql.
•   help [arg], \h [arg], \? [arg], ? [arg]
Display a help message listing the available mysql commands.
If you provide an argument to the help command, mysql uses it as a search string to access server-side help from the contents of the MySQL Reference Manual. For more information, see the section called “MYSQL CLIENT SERVER-SIDE HELP”.
•   charset charset_name, \C charset_name
Change the default character set and issue a SET NAMES statement. This enables the character set to remain synchronized on the client and server if mysql is run with auto-reconnect enabled (which is not recommended), because the specified character set is used for reconnects.
•   clear, \c
Clear the current input. Use this if you change your mind about executing the statement that you are entering.
•   connect [db_name [host_name]], \r [db_name [host_name]]
Reconnect to the server. The optional database name and host name arguments may be given to specify the default database or the host where the server is running. If omitted, the current values are used.
If the connect command specifies a host name argument, that host takes precedence over any --dns-srv-name option given at mysql startup to specify a DNS SRV record.
•   delimiter str, \d str
Change the string that mysql interprets as the separator between SQL statements. The default is the semicolon character (;).
The delimiter string can be specified as an unquoted or quoted argument on the delimiter command line. Quoting can be done with either single quote ('), double quote ("), or backtick (`) characters. To include a quote within a quoted string, either quote the string with a different quote character or escape the quote with a backslash (\) character. Backslash should be avoided outside of quoted strings because it is the escape character for MySQL. For an unquoted argument, the delimiter is read up to the first space or end of line. For a quoted argument, the delimiter is read up to the matching quote on the line.
mysql interprets instances of the delimiter string as a statement delimiter anywhere it occurs, except within quoted strings. Be careful about defining a delimiter that might occur within other words. For example, if you define the delimiter as X, it is not possible to use the word INDEX in statements.  mysql interprets this as INDE followed by the delimiter X.
When the delimiter recognized by mysql is set to something other than the default of ;, instances of that character are sent to the server without interpretation. However, the server itself still interprets ; as a statement delimiter and processes statements accordingly. This behavior on the server side comes into play for multiple-statement execution (see Multiple Statement Execution Support[3]), and for parsing the body of stored procedures and functions, triggers, and events (see Section 25.1, “Defining Stored Programs”).
•   edit, \e
Edit the current input statement.  mysql checks the values of the EDITOR and VISUAL environment variables to determine which editor to use. The default editor is vi if neither variable is set.
The edit command works only in Unix.
•   ego, \G
Send the current statement to the server to be executed and display the result using vertical format.
•   exit, \q
Exit mysql.
•   go, \g
Send the current statement to the server to be executed.
•   nopager, \n
Disable output paging. See the description for pager.
The nopager command works only in Unix.
•   notee, \t
Disable output copying to the tee file. See the description for tee.
•   nowarning, \w
Disable display of warnings after each statement.
•   pager [command], \P [command]
Enable output paging. By using the --pager option when you invoke mysql, it is possible to browse or search query results in interactive mode with Unix programs such as less, more, or any other similar program. If you specify no value for the option, mysql checks the value of the PAGER environment variable and sets the pager to that. Pager functionality works only in interactive mode.
Output paging can be enabled interactively with the pager command and disabled with nopager. The command takes an optional argument; if given, the paging program is set to that. With no argument, the pager is set to the pager that was set on the command line, or stdout if no pager was specified.
Output paging works only in Unix because it uses the popen() function, which does not exist on Windows. For Windows, the tee option can be used instead to save query output, although it is not as convenient as pager for browsing output in some situations.
•   print, \p
Print the current input statement without executing it.
•   prompt [str], \R [str]
Reconfigure the mysql prompt to the given string. The special character sequences that can be used in the prompt are described later in this section.
If you specify the prompt command with no argument, mysql resets the prompt to the default of mysql>.
•   query_attributes name value [name value ...]
Define query attributes that apply to the next query sent to the server. For discussion of the purpose and use of query attributes, see Section 9.6, “Query Attributes”.
The query_attributes command follows these rules:
•   The format and quoting rules for attribute names and values are the same as for the delimiter command.
•   The command permits up to 32 attribute name/value pairs. Names and values may be up to 1024 characters long. If a name is given without a value, an error occurs.
•   If multiple query_attributes commands are issued prior to query execution, only the last command applies. After sending the query, mysql clears the attribute set.
•   If multiple attributes are defined with the same name, attempts to retrieve the attribute value have an undefined result.
•   An attribute defined with an empty name cannot be retrieved by name.
•   If a reconnect occurs while mysql executes the query, mysql restores the attributes after reconnecting so the query can be executed again with the same attributes.
•   quit, \q
•   rehash, \#
Rebuild the completion hash that enables database, table, and column name completion while you are entering statements. (See the description for the --auto-rehash option.)
•   resetconnection, \x
Reset the connection to clear the session state. This includes clearing any current query attributes defined using the query_attributes command.
Resetting a connection has effects similar to mysql_change_user() or an auto-reconnect except that the connection is not closed and reopened, and re-authentication is not done. See mysql_change_user()[4], and Automatic Reconnection Control[5].
This example shows how resetconnection clears a value maintained in the session state:
mysql> SELECT LAST_INSERT_ID(3); +-------------------+ | LAST_INSERT_ID(3) | +-------------------+ |                 3 | +-------------------+ mysql> SELECT LAST_INSERT_ID(); +------------------+ | LAST_INSERT_ID() | +------------------+ |                3 | +------------------+ mysql> resetconnection; mysql> SELECT LAST_INSERT_ID(); +------------------+ | LAST_INSERT_ID() | +------------------+ |                0 | +------------------+
•   source file_name, \. file_name
Read the named file and executes the statements contained therein. On Windows, specify path name separators as / or \\.
Quote characters are taken as part of the file name itself. For best results, the name should not include space characters.
•   status, \s
Provide status information about the connection and the server you are using. If you are running with --safe-updates enabled, status also prints the values for the mysql variables that affect your queries.
•   system command, \! command
Execute the given command using your default command interpreter.
Prior to MySQL 8.0.19, the system command works only in Unix. As of 8.0.19, it also works on Windows.
•   tee [file_name], \T [file_name]
By using the --tee option when you invoke mysql, you can log statements and their output. All the data displayed on the screen is appended into a given file. This can be very useful for debugging purposes also.  mysql flushes results to the file after each statement, just before it prints its next prompt. Tee functionality works only in interactive mode.
You can enable this feature interactively with the tee command. Without a parameter, the previous file is used. The tee file can be disabled with the notee command. Executing tee again re-enables logging.
•   use db_name, \u db_name
Use db_name as the default database.
•   warnings, \W
Enable display of warnings after each statement (if there are any).
Here are a few tips about the pager command:
•   You can use it to write to a file and the results go only to the file:
mysql> pager cat > /tmp/log.txt
You can also pass any options for the program that you want to use as your pager:
mysql> pager less -n -i -S
•   In the preceding example, note the -S option. You may find it very useful for browsing wide query results. Sometimes a very wide result set is difficult to read on the screen. The -S option to less can make the result set much more readable because you can scroll it horizontally using the left-arrow and right-arrow keys. You can also use -S interactively within less to switch the horizontal-browse mode on and off. For more information, read the less manual page:
man less
•   The -F and -X options may be used with less to cause it to exit if output fits on one screen, which is convenient when no scrolling is necessary:
mysql> pager less -n -i -S -F -X
•   You can specify very complex pager commands for handling query output:
mysql> pager cat | tee /dr1/tmp/res.txt \ | tee /dr2/tmp/res2.txt | less -n -i -S
In this example, the command would send query results to two files in two different directories on two different file systems mounted on /dr1 and /dr2, yet still display the results onscreen using less.
You can also combine the tee and pager functions. Have a tee file enabled and pager set to less, and you are able to browse the results using the less program and still have everything appended into a file the same time. The difference between the Unix tee used with the pager command and the mysql built-in tee command is that the built-in tee works even if you do not have the Unix tee available. The built-in tee also logs everything that is printed on the screen, whereas the Unix tee used with pager does not log quite that much. Additionally, tee file logging can be turned on and off interactively from within mysql. This is useful when you want to log some queries to a file, but not others.
The prompt command reconfigures the default mysql> prompt. The string for defining the prompt can contain the following special sequences.
You can set the prompt in several ways:
•   Use an environment variable.  You can set the MYSQL_PS1 environment variable to a prompt string. For example:
export MYSQL_PS1="(\u@\h) [\d]> "
•   Use a command-line option.  You can set the --prompt option on the command line to mysql. For example:
shell> mysql --prompt="(\u@\h) [\d]> " (user@host) [database]>
•   Use an option file.  You can set the prompt option in the [mysql] group of any MySQL option file, such as /etc/my.cnf or the .my.cnf file in your home directory. For example:
[mysql] prompt=(\\u@\\h) [\\d]>\\_
In this example, note that the backslashes are doubled. If you set the prompt using the prompt option in an option file, it is advisable to double the backslashes when using the special prompt options. There is some overlap in the set of permissible prompt options and the set of special escape sequences that are recognized in option files. (The rules for escape sequences in option files are listed in Section 4.2.2.2, “Using Option Files”.) The overlap may cause you problems if you use single backslashes. For example, \s is interpreted as a space rather than as the current seconds value. The following example shows how to define a prompt within an option file to include the current time in hh:mm:ss> format:
[mysql] prompt="\\r:\\m:\\s> "
•   Set the prompt interactively.  You can change your prompt interactively by using the prompt (or \R) command. For example:
mysql> prompt (\u@\h) [\d]>\_ PROMPT set to '(\u@\h) [\d]>\_' (user@host) [database]> (user@host) [database]> prompt Returning to default PROMPT of mysql> mysql>
The mysql client can do these types of logging for statements executed interactively:
•   On Unix, mysql writes the statements to a history file. By default, this file is named .mysql_history in your home directory. To specify a different file, set the value of the MYSQL_HISTFILE environment variable.
•   On all platforms, if the --syslog option is given, mysql writes the statements to the system logging facility. On Unix, this is syslog; on Windows, it is the Windows Event Log. The destination where logged messages appear is system dependent. On Linux, the destination is often the /var/log/messages file.
The following discussion describes characteristics that apply to all logging types and provides information specific to each logging type.
•   How Logging Occurs
•   Controlling the History File
•   syslog Logging Characteristics How Logging Occurs
For each enabled logging destination, statement logging occurs as follows:
•   Statements are logged only when executed interactively. Statements are noninteractive, for example, when read from a file or a pipe. It is also possible to suppress statement logging by using the --batch or --execute option.
•   Statements are ignored and not logged if they match any pattern in the “ignore” list. This list is described later.
•   mysql logs each nonignored, nonempty statement line individually.
•   If a nonignored statement spans multiple lines (not including the terminating delimiter), mysql concatenates the lines to form the complete statement, maps newlines to spaces, and logs the result, plus a delimiter.
Consequently, an input statement that spans multiple lines can be logged twice. Consider this input:
mysql> SELECT -> 'Today is' -> , -> CURDATE() -> ;
In this case, mysql logs the “SELECT”, “'Today is'”, “,”, “CURDATE()”, and “;” lines as it reads them. It also logs the complete statement, after mapping SELECT\n'Today is'\n,\nCURDATE() to SELECT 'Today is' , CURDATE(), plus a delimiter. Thus, these lines appear in logged output:
SELECT 'Today is' , CURDATE() ; SELECT 'Today is' , CURDATE();
mysql ignores for logging purposes statements that match any pattern in the “ignore” list. By default, the pattern list is "*IDENTIFIED*:*PASSWORD*", to ignore statements that refer to passwords. Pattern matching is not case-sensitive. Within patterns, two characters are special:
•   ?  matches any single character.
•   * matches any sequence of zero or more characters.
To specify additional patterns, use the --histignore option or set the MYSQL_HISTIGNORE environment variable. (If both are specified, the option value takes precedence.) The value should be a list of one or more colon-separated patterns, which are appended to the default pattern list.
Patterns specified on the command line might need to be quoted or escaped to prevent your command interpreter from treating them specially. For example, to suppress logging for UPDATE and DELETE statements in addition to statements that refer to passwords, invoke mysql like this:
mysql --histignore="*UPDATE*:*DELETE*"
Controlling the History File
The .mysql_history file should be protected with a restrictive access mode because sensitive information might be written to it, such as the text of SQL statements that contain passwords. See Section 6.1.2.1, “End- User Guidelines for Password Security”. Statements in the file are accessible from the mysql client when the up-arrow key is used to recall the history. See Disabling Interactive History.
If you do not want to maintain a history file, first remove .mysql_history if it exists. Then use either of the following techniques to prevent it from being created again:
•   Set the MYSQL_HISTFILE environment variable to /dev/null. To cause this setting to take effect each time you log in, put it in one of your shell's startup files.
•   Create .mysql_history as a symbolic link to /dev/null; this need be done only once:
ln -s /dev/null $HOME/.mysql_history syslog Logging Characteristics
If the --syslog option is given, mysql writes interactive statements to the system logging facility. Message logging has the following characteristics.
Logging occurs at the “information” level. This corresponds to the LOG_INFO priority for syslog on Unix/Linux syslog capability and to EVENTLOG_INFORMATION_TYPE for the Windows Event Log. Consult your system documentation for configuration of your logging capability.
Message size is limited to 1024 bytes.
Messages consist of the identifier MysqlClient followed by these values:
•   SYSTEM_USER
The operating system user name (login name) or -- if the user is unknown.
•   MYSQL_USER
The MySQL user name (specified with the --user option) or -- if the user is unknown.
•   CONNECTION_ID:
The client connection identifier. This is the same as the CONNECTION_ID() function value within the session.
•   DB_SERVER
The server host or -- if the host is unknown.
•   DB
The default database or -- if no database has been selected.
•   QUERY
The text of the logged statement.
MYSQL CLIENT SERVER-SIDE HELP mysql> help search_string
If you provide an argument to the help command, mysql uses it as a search string to access server-side help from the contents of the MySQL Reference Manual. The proper operation of this command requires that the help tables in the mysql database be initialized with help topic information (see Section 5.1.17, “Server-Side Help Support”).
If there is no match for the search string, the search fails:
mysql> help me Nothing found Please try to run 'help contents' for a list of all accessible topics
Use help contents to see a list of the help categories:
mysql> help contents You asked for help about help category: "Contents" For more information, type 'help <item>', where <item> is one of the following categories: Account Management Administration Data Definition Data Manipulation Data Types Functions Functions and Modifiers for Use with GROUP BY Geographic Features Language Structure Plugins Storage Engines Stored Routines Table Maintenance Transactions Triggers
If the search string matches multiple items, mysql shows a list of matching topics: