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MARIADB(1) MariaDB Database System MARIADB(1)
mariadb - the MariaDB command-line tool (mysql is now a symlink to
mariadb)
mariadb [options] db_name
mariadb is a simple SQL shell (with GNU readline capabilities). It
supports interactive and non-interactive use. When used
interactively, query results are presented in an ASCII-table
format. When used non-interactively (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 mariadb 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
mariadb_use_result() C API function in the client/server library
rather than mysql_store_result().
Using mariadb is very easy. Invoke it from the prompt of your
command interpreter as follows:
shell> mariadb db_name
Or:
shell> mariadb --user=user_name --password=your_password db_name
Then type an SQL statement, end it with “;”, \g, or \G and press
Enter.
Typing Control-C causes mariadb to attempt to kill the current
statement. If this cannot be done, or Control-C is typed again
before the statement is killed, mariadb exits.
You can execute SQL statements in a script file (batch file) like
this:
shell> mariadb db_name < script.sql > output.tab
mariadb supports the following options, which can be specified on
the command line or in the [mariadb], [client], [client-server] or
[client-mariadb] option file groups. mariadb also supports the
options for processing option files.
• --help, -?, -I
Display a help message and exit.
• --abort-source-on-error
Abort 'source filename' operations in case of errors.
• --auto-rehash
Enable automatic rehashing. This option is on by default,
which enables database, table, and column name completion. Use
--disable-auto-rehash, --no-auto-rehash, or
--skip-auto-rehash to disable rehashing. That causes mariadb
to start faster, but you must issue the rehash command if you
want to use name completion.
To complete a name, enter the first part and press Tab. If the
name is unambiguous, mariadb 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.
• --auto-vertical-output
Automatically switch to vertical output mode if the result is
wider than the terminal width.
• --batch, -B
Print results using tab as the column separator, with each row
on a new line. With this option, mariadb 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-mode
Binary mode allows certain character sequences to be processed
as data that would otherwise be treated with a special meaning
by the parser. Specifically, this switch turns off parsing of
all client commands except \C and DELIMITER in non-interactive
mode (i.e., when binary mode is combined with either 1) piped
input, 2) the --batch mariadb option, or 3) the 'source'
command). Also, in binary mode, occurrences of '\r\n' and
ASCII '\0' are preserved within strings, whereas by default,
'\r\n' is translated to '\n' and '\0' is disallowed in user
input.
• --character-sets-dir=path
The directory where character sets are installed.
• --column-names
Write column names in results.
• --column-type-info, -m
Display result set metadata.
• --comments, -c
Whether to preserve comments in statements sent to the server.
The default is --skip-comments (discard comments), enable with
--comments (preserve comments).
• --compress, -C
Compress all information sent between the client and the
server if both support compression.
• --connect-timeout=seconds
Set the number of seconds before connection timeout. (Default
value is 0.)
• --database=db_name, -D db_name
The database to use.
• --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-check
Print some debugging information when the program exits.
• --debug-info, -T
Prints debugging information and memory and CPU usage
statistics when the program exits.
• --default-auth=name
Default authentication client-side plugin to use.
• --default-character-set=charset_name
Use charset_name as the default character set for the client
and connection.
A common issue that can occur when the operating system uses
utf8 or another multi-byte character set is that output from
the mariadb client is formatted incorrectly, due to the fact
that the MariaDB client uses the latin1 character set by
default. You can usually fix such issues by using this option
to force the client to use the system character set instead.
• --defaults-extra-file=filename
Set filename as the file to read default options from after
the global defaults files has been read. Must be given as
first option.
• --defaults-file=filename
Set filename as the file to read default options from,
override global defaults files. Must be given as first option.
• --defaults-group-suffix=suffix
In addition to the groups named on the command line, read
groups that have the given suffix.
• --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 (“;”). mariadb 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
“MARIADB COMMANDS”.
• --enable-cleartext-plugin
Obsolete option. Exists only for MySQL compatibility.
• --execute=statement, -e statement
Execute the statement and quit. Disables --force and history
file. The default output format is like that produced with
--batch.
• --force, -f
Continue even if an SQL error occurs. Sets --abort-source-on-
error to 0.
• --host=host_name, -h host_name
Connect to the MariaDB server on the given host.
• --html, -H
Produce HTML output.
• --ignore-spaces, -i
Ignore spaces after function names. Allows one to have spaces
(including tab characters and new line characters) between
function name and '('. The drawback is that this causes built
in functions to become reserved words.
• --init-command=str
SQL Command to execute when connecting to the MariaDB server.
Will automatically be re-executed when reconnecting.
• --line-numbers
Write line numbers for errors. Disable this with
--skip-line-numbers.
• --local-infile[={0|1}]
Enable or disable LOCAL capability for LOAD DATA INFILE. With
no value, the option enables LOCAL. The option may be given as
--local-infile=0 or --local-infile=1 to explicitly disable or
enable LOCAL. Enabling LOCAL has no effect if the server does
not also support it.
• --max-allowed-packet=num
Set the maximum packet length to send to or receive from the
server. (Default value is 16MB, largest 1GB.)
• --max-join-size=num
Set the automatic limit for rows in a join when using
--safe-updates. (Default value is 1,000,000.)
• --named-commands, -G
Enable named mariadb commands. Long-format commands are
allowed, 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 “MARIADB COMMANDS”.
Disabled by default.
•• --net-buffer-length=size
Set the buffer size for TCP/IP and socket communication.
(Default value is 16KB.)
• --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.
• --no-defaults
Do not read default options from any option file. This must be
given as the first argument.
• --one-database, -o
Ignore statements except those those that occur while the
default database is the one named on the command line. This
filtering is limited, and based only on USE statements. This
is useful for skipping updates to other databases in the
binary log.
• --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 “MARIADB COMMANDS”, discusses output paging
further.
• --password[=password], -p[password]
The password to use when connecting to the server. If you use
the short option form (-p), you cannot have a space between
the option and the password. If you omit the password value
following the --password or -p option on the command line,
mariadb prompts for one.
Specifying a password on the command line should be considered
insecure. You can use an option file to avoid giving the
password on the command line.
• --pipe, -W
On Windows, connect to the server via a named pipe. This
option applies only if the server supports named-pipe
connections.
• --plugin-dir=dir_name
Directory for client-side plugins.
• --port=port_num, -P port_num
The TCP/IP port number to use for the connection or 0 for
default to, in order of preference, my.cnf, $MYSQL_TCP_PORT,
/etc/services, built-in default (3306). Forces --protocol=tcp
when specified on the command line without other connection
properties.
• --print-defaults
Print the program argument list and exit. This must be given
as the first argument.
• --progress-reports
Get progress reports for long running commands (such as ALTER
TABLE). (Defaults to on; use --skip-progress-reports to
disable.)
• --prompt=format_str
Set the prompt to the specified format. The special sequences
that the prompt can contain are described in the section
called “MARIADB COMMANDS”.
• --protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server.
It is useful when the other connection parameters normally
would cause a protocol to be used other than the one you want.
• --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, mariadb 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:
% mariadb
mariadb> SELECT CHAR(92);
+----------+
| CHAR(92) |
+----------+
| \ |
+----------+
% mariadb -s
mariadb> SELECT CHAR(92);
CHAR(92)
\\
% mariadb -s -r
mariadb> 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. Enabled by default, to disable use
--skip-reconnect or --disable-reconnect.
• --safe-updates, --i-am-a-dummy, -U
Allow only those UPDATE and DELETE statements that specify
which rows to modify by using key values. If you have set this
option in an option file, you can override it by using
--safe-updates on the command line. See the section called
“MARIADB TIPS”, for more information about this option.
• --secure-auth
Do not send passwords to the server in old (pre-4.1.1) format.
This prevents connections except for servers that use the
newer password format.
• --select-limit=limit
Set automatic limit for SELECT when using --safe-updates.
(Default value is 1,000.)
• --server-arg=name
Send name as a parameter to the embedded server.
• --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).
• --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-auto-rehash
Disable automatic rehashing. Synonym for
--disable-auto-rehash.
• --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.
• --socket=path, -S path
For connections to localhost, the Unix socket file to use, or,
on Windows, the name of the named pipe to use. Forces
--protocol=socket when specified on the command line without
other connection properties; on Windows, forces
--protocol=pipe.
• --ssl
Enable SSL for connection (automatically enabled with other
flags). Disable with --skip-ssl.
• --ssl-ca=name
CA file in PEM format (check OpenSSL docs, implies --ssl).
• --ssl-capath=name
CA directory (check OpenSSL docs, implies --ssl).
• --ssl-cert=name
X509 cert in PEM format (check OpenSSL docs, implies --ssl).
• --ssl-cipher=name
SSL cipher to use (check OpenSSL docs, implies --ssl).
• --ssl-key=name
X509 key in PEM format (check OpenSSL docs, implies --ssl).
• --ssl-crl=name
Certificate revocation list (check OpenSSL docs, implies
--ssl).
• --ssl-crlpath=name
Certificate revocation list path (check OpenSSL docs, implies
--ssl).
• --ssl-verify-server-cert
Verify server's "Common Name" in its cert against hostname
used when connecting. This option is disabled by default.
• --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 “MARIADB
COMMANDS”, discusses tee files further.
• --unbuffered, -n
Flush the buffer after each query.
• --user=user_name, -u user_name
The MariaDB user name to use when connecting to the server.
• --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. The output when --xml is used with
mariadb matches that of mariadb-dump --xml. See
mariadb-dump(1) for details.
The XML output also uses an XML namespace, as shown here:
shell> mariadb --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>
You can also set the following variables by using
--var_name=value.
• connect_timeout
The number of seconds before connection timeout. (Default
value is 0.)
• max_allowed_packet
The maximum packet length to send to or receive from the
server. (Default value is 16MB.)
• max_join_size
The automatic limit for rows in a join when using
--safe-updates. (Default value is 1,000,000.)
• net_buffer_length
The buffer size for TCP/IP and socket communication.
(Default value is 16KB.)
• select_limit
The automatic limit for SELECT statements when using
--safe-updates. (Default value is 1,000.)
On Unix, the mariadb client writes a record of executed
statements to a history file. By default, this file is named
.mariadb_history and is created in your home directory. For
backwards compatibility .mariadb_history will be used if
present and .mariadb_history is missing. To specify a
different file, set the value of the MARIADB_HISTFILE
environment variable. The environment variable MYSQL_HISTFILE
will be used if MARIADB_HISTFILE isn't present.
The .mariadb_history 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.
If you do not want to maintain a history file, first remove
.mariadb_history if it exists, and then use either of the
following techniques:
• Set the MARIADB_HISTFILE variable to /dev/null. To cause
this setting to take effect each time you log in, put the
setting in one of your shell's startup files.
• Create .mariadb_history as a symbolic link to /dev/null:
shell> ln -s /dev/null $HOME/.mariadb_history
You need do this only once.
mariadb sends each SQL statement that you issue to the server to
be executed. There is also a set of commands that mariadb itself
interprets. For a list of these commands, type help or \h at the
mariadb> prompt:
mariadb> help
List of all MariaDB commands:
Note that all text commands must be first on line and end with ';'
? (\?) Synonym for 'help'.
clear (\c) Clear command.
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 mariadb server, display result vertically.
exit (\q) Exit mariadb. Same as quit.
go (\g) Send command to mariadb 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 mariadb prompt.
quit (\q) Quit mariadb.
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.
For server side help, type 'help contents'
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 multi-line /* ... */
comments is not supported.
• help [arg], \h [arg], \? [arg], ? [arg]
Display a help message listing the available mariadb commands.
If you provide an argument to the help command, mariadb uses
it as a search string to access server-side help. For more
information, see the section called “MARIADB 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 mariadb 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.
• delimiter str, \d str
Change the string that mariadb interprets as the separator
between SQL statements. The default is the semicolon character
(“;”).
The delimiter can be specified as an unquoted or quoted
argument. Quoting can be done with either single quote (') or
double quote (") characters. To include a quote within a
quoted string, either quote the string with the other 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 MariaDB. 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.
When the delimiter recognized by mariadb 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, and for
parsing the body of stored procedures and functions, triggers,
and events.
• edit, \e
Edit the current input statement. mariadb 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 mariadb.
• 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
Enable display of warnings after each statement.
• pager [command], \P [command]
Enable output paging. By using the --pager option when you
invoke mariadb, 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, mariadb 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 mariadb 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, mariadb
resets the prompt to the default of mariadb>.
• quit, \q
Exit mariadb.
• 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.)
• source file_name, \. file_name
Read the named file and executes the statements contained
therein. On Windows, you can specify path name separators as /
or \\.
• status, \s
Provide status information about the connection and the server
you are using. If you are running in --safe-updates mode,
status also prints the values for the mariadb variables that
affect your queries.
• system command, \! command
Execute the given command using your default command
interpreter.
The system command works only in Unix.
• tee [file_name], \T [file_name]
By using the --tee option when you invoke mariadb, 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. mariadb 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:
mariadb> pager cat > /tmp/log.txt
You can also pass any options for the program that you want to
use as your pager:
mariadb> 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:
shell> 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:
mariadb> pager less -n -i -S -F -X
• You can specify very complex pager commands for handling query
output:
mariadb> 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 via 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 mariadb 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 mariadb. This is
useful when you want to log some queries to a file, but not
others.
The prompt command reconfigures the default mariadb> prompt. The
string for defining the prompt can contain the following special
sequences.
┌────────┬────────────────────────────┐
│ Option │ Description │
├────────┼────────────────────────────┤
│ \c │ A counter that │
│ │ increments for each │
│ │ statement you issue │
├────────┼────────────────────────────┤
│ \D │ The full current date │
├────────┼────────────────────────────┤
│ \d │ The default database │
├────────┼────────────────────────────┤
│ \h │ The server host │
├────────┼────────────────────────────┤
│ \l │ The current delimiter │
│ │ (new in 5.1.12) │
├────────┼────────────────────────────┤
│ \m │ Minutes of the current │
│ │ time │
├────────┼────────────────────────────┤
│ \n │ A newline character │
├────────┼────────────────────────────┤
│ \O │ The current month in │
│ │ three-letter format │
│ │ (Jan, Feb, ...) │
├────────┼────────────────────────────┤
│ \o │ The current month in │
│ │ numeric format │
├────────┼────────────────────────────┤
│ \P │ am/pm │
├────────┼────────────────────────────┤
│ \p │ The current TCP/IP port │
│ │ or socket file │
├────────┼────────────────────────────┤
│ \R │ The current time, in │
│ │ 24-hour military time │
│ │ (0–23) │
├────────┼────────────────────────────┤
│ \r │ The current time, │
│ │ standard 12-hour time │
│ │ (1–12) │
├────────┼────────────────────────────┤
│ \S │ Semicolon │
├────────┼────────────────────────────┤
│ \s │ Seconds of the current │
│ │ time │
├────────┼────────────────────────────┤
│ \t │ A tab character │
├────────┼────────────────────────────┤
│ \U │ │
│ │ Your full │
│ │ user_name@host_name │
│ │ account name │
├────────┼────────────────────────────┤
│ \u │ Your user name │
├────────┼────────────────────────────┤
│ \v │ The server version │
├────────┼────────────────────────────┤
│ \w │ The current day of the │
│ │ week in three-letter │
│ │ format (Mon, Tue, ...) │
├────────┼────────────────────────────┤
│ \Y │ The current year, four │
│ │ digits │
├────────┼────────────────────────────┤
│ \y │ The current year, two │
│ │ digits │
├────────┼────────────────────────────┤
│ \_ │ A space │
├────────┼────────────────────────────┤
│ \ │ A space (a space follows │
│ │ the backslash) │
├────────┼────────────────────────────┤
│ \' │ Single quote │
├────────┼────────────────────────────┤
│ \" │ Double quote │
├────────┼────────────────────────────┤
│ \\ │ A literal “\” backslash │
│ │ character │
├────────┼────────────────────────────┤
│ \x │ │
│ │ x, for any “x” not │
│ │ listed above │
└────────┴────────────────────────────┘
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:
shell> export MYSQL_PS1="(\u@\h) [\d]> "
• Use a command-line option. You can set the --prompt option on
the command line to mariadb. For example:
shell> mariadb --prompt="(\u@\h) [\d]> "
(user@host) [database]>
• Use an option file. You can set the prompt option in the
[mariadb] group of any MariaDB option file, such as
/etc/my.cnf or the .my.cnf file in your home directory. For
example:
[mariadb]
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 allowable
prompt options and the set of special escape sequences that
are recognized in 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:
[mariadb]
prompt="\\r:\\m:\\s> "
• Set the prompt interactively. You can change your prompt
interactively by using the prompt (or \R) command. For
example:
mariadb> prompt (\u@\h) [\d]>\_
PROMPT set to '(\u@\h) [\d]>\_'
(user@host) [database]>
(user@host) [database]> prompt
Returning to default PROMPT of mariadb>
mariadb>
mariadb> help search_string
If you provide an argument to the help command, mariadb uses it as
a search string to access server-side help. The proper operation
of this command requires that the help tables in the mysql
database be initialized with help topic information.
If there is no match for the search string, the search fails:
mariadb> 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:
mariadb> 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, mariadb shows a list
of matching topics:
mariadb> help logs
Many help items for your request exist.
To make a more specific request, please type 'help <item>',
where <item> is one of the following topics:
SHOW
SHOW BINARY LOGS
SHOW ENGINE
SHOW LOGS
Use a topic as the search string to see the help entry for that
topic:
mariadb> help show binary logs
Name: 'SHOW BINARY LOGS'
Description:
Syntax:
SHOW BINARY LOGS
SHOW MASTER LOGS
Lists the binary log files on the server. This statement is used as
part of the procedure described in [purge-binary-logs], that shows how
to determine which logs can be purged.
mariadb> SHOW BINARY LOGS;
+---------------+-----------+
| Log_name | File_size |
+---------------+-----------+
| binlog.000015 | 724935 |
| binlog.000016 | 733481 |
+---------------+-----------+
The mariadb client typically is used interactively, like this:
shell> mariadb db_name
However, it is also possible to put your SQL statements in a file
and then tell mariadb to read its input from that file. To do so,
create a text file text_file that contains the statements you wish
to execute. Then invoke mariadb as shown here:
shell> mariadb db_name < text_file
If you place a USE db_name statement as the first statement in the
file, it is unnecessary to specify the database name on the
command line:
shell> mariadb < text_file
If you are already running mariadb, you can execute an SQL script
file using the source command or \. command:
mariadb> source file_name
mariadb> \. file_name
Sometimes you may want your script to display progress information
to the user. For this you can insert statements like this:
SELECT '<info_to_display>' AS ' ';
The statement shown outputs <info_to_display>.
You can also invoke mariadb with the --verbose option, which
causes each statement to be displayed before the result that it
produces.
mariadb ignores Unicode byte order mark (BOM) characters at the
beginning of input files. Presence of a BOM does not cause mariadb
to change its default character set. To do that, invoke mariadb
with an option such as --default-character-set=utf8.
This section describes some techniques that can help you use
mariadb more effectively.
Displaying Query Results Vertically
Some query results are much more readable when displayed
vertically, instead of in the usual horizontal table format.
Queries can be displayed vertically by terminating the query with
\G instead of a semicolon. For example, longer text values that
include newlines often are much easier to read with vertical
output:
mariadb> SELECT * FROM mails WHERE LENGTH(txt) < 300 LIMIT 300,1\G
*************************** 1. row ***************************
msg_nro: 3068
date: 2000-03-01 23:29:50
time_zone: +0200
mail_from: Monty
reply: [email protected]
mail_to: "Thimble Smith" <[email protected]>
sbj: UTF-8
txt: >>>>> "Thimble" == Thimble Smith writes:
Thimble> Hi. I think this is a good idea. Is anyone familiar
Thimble> with UTF-8 or Unicode? Otherwise, I'll put this on my
Thimble> TODO list and see what happens.
Yes, please do that.
Regards,
Monty
file: inbox-jani-1
hash: 190402944
1 row in set (0.09 sec)
Using the --safe-updates Option
For beginners, a useful startup option is --safe-updates (or
--i-am-a-dummy, which has the same effect). It is helpful for
cases when you might have issued a DELETE FROM tbl_name statement
but forgotten the WHERE clause. Normally, such a statement deletes
all rows from the table. With --safe-updates, you can delete rows
only by specifying the key values that identify them. This helps
prevent accidents.
When you use the --safe-updates option, mariadb issues the
following statement when it connects to the MariaDB server:
SET sql_safe_updates=1, sql_select_limit=1000, sql_max_join_size=1000000;
The SET statement has the following effects:
• You are not allowed to execute an UPDATE or DELETE statement
unless you specify a key constraint in the WHERE clause or
provide a LIMIT clause (or both). For example:
UPDATE tbl_name SET not_key_column=val WHERE key_column=val;
UPDATE tbl_name SET not_key_column=val LIMIT 1;
• The server limits all large SELECT results to 1,000 rows
unless the statement includes a LIMIT clause.
• The server aborts multiple-table SELECT statements that
probably need to examine more than 1,000,000 row combinations.
To specify limits different from 1,000 and 1,000,000, you can
override the defaults by using the --select-limit and
--max-join-size options:
shell> mariadb --safe-updates --select-limit=500 --max-join-size=10000
Disabling mariadb Auto-Reconnect
If the mariadb client loses its connection to the server while
sending a statement, it immediately and automatically tries to
reconnect once to the server and send the statement again.
However, even if mariadb succeeds in reconnecting, your first
connection has ended and all your previous session objects and
settings are lost: temporary tables, the autocommit mode, and
user-defined and session variables. Also, any current transaction
rolls back. This behavior may be dangerous for you, as in the
following example where the server was shut down and restarted
between the first and second statements without you knowing it:
mariadb> SET @a=1;
Query OK, 0 rows affected (0.05 sec)
mariadb> INSERT INTO t VALUES(@a);
ERROR 2006: MariaDB server has gone away
No connection. Trying to reconnect...
Connection id: 1
Current database: test
Query OK, 1 row affected (1.30 sec)
mariadb> SELECT * FROM t;
+------+
| a |
+------+
| NULL |
+------+
1 row in set (0.05 sec)
The @a user variable has been lost with the connection, and after
the reconnection it is undefined. If it is important to have
mariadb terminate with an error if the connection has been lost,
you can start the mariadb client with the --skip-reconnect option.
Copyright 2007-2008 MySQL AB, 2008-2010 Sun Microsystems, Inc.,
2010-2025 MariaDB Foundation
This documentation is free software; you can redistribute it
and/or modify it only under the terms of the GNU General Public
License as published by the Free Software Foundation; version 2 of
the License.
This documentation is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with the program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1335 USA or see http://www.gnu.org/licenses/.
1. Bug#25946
http://bugs.mysql.com/bug.php?id=25946
For more information, please refer to the MariaDB Knowledge Base,
available online at https://mariadb.com/kb/
MariaDB Foundation (http://www.mariadb.org/).
This page is part of the MariaDB (MariaDB database server)
project. Information about the project can be found at
⟨http://mariadb.org/⟩. If you have a bug report for this manual
page, see ⟨https://mariadb.com/kb/en/mariadb/reporting-bugs/⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/MariaDB/server⟩ on 2025-08-11. (At that time,
the date of the most recent commit that was found in the
repository was 2025-08-04.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
MariaDB 11.8 5 March 2025 MARIADB(1)
Pages that refer to this page: mariadb(1)
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