MySQL8.0大师之路：第9章：MySQL教程-9.8 MySQL高效的使用自带帮助
1.# mysql --help或者# mysql -?
mysqlVer 8.0.19 for linux-glibc2.12 on x86_64 (MySQL Community Server - GPL)
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Usage: mysql
-?, --help Display this help and exit.
-I, --help Synonym for -?
--auto-rehash Enable automatic rehashing. One doesn't need to use
'rehash' to get table and field completion, but startup
and reconnecting may take a longer time. Disable with
--disable-auto-rehash.
(Defaults to on; use --skip-auto-rehash to disable.)
-A, --no-auto-rehash
No automatic rehashing. One has to use 'rehash' to get
table and field completion. This gives a quicker start of
mysql and disables rehashing on reconnect.
--auto-vertical-output
Automatically switch to vertical output mode if the
result is wider than the terminal width.
-B, --batch Don't use history file. Disable interactive behavior.
(Enables --silent.)
--bind-address=name IP address to bind to.
--binary-as-hex Print binary data as hex
--character-sets-dir=name
Directory for character set files.
--column-type-infoDisplay column type information.
-c, --comments Preserve comments. Send comments to the server. The
default is --skip-comments (discard comments), enable
with --comments.
-C, --compress Use compression in server/client protocol.
-#, --debug[=#] This is a non-debug version. Catch this and exit.
--debug-check This is a non-debug version. Catch this and exit.
-T, --debug-info This is a non-debug version. Catch this and exit.
-D, --database=name Database to use.
--default-character-set=name
Set the default character set.
--delimiter=name Delimiter to be used.
--enable-cleartext-plugin
Enable/disable the clear text authentication plugin.
-e, --execute=nameExecute command and quit. (Disables --force and history
file.)
-E, --vertical Print the output of a query (rows) vertically.
-f, --force Continue even if we get an SQL error.
--histignore=name A colon-separated list of patterns to keep statements
from getting logged into syslog and mysql history.
-G, --named-commands
Enable named commands. Named commands mean this program's
internal commands; see mysql> help . When enabled, the
named commands can be used from any line of the query,
otherwise only from the first line, before an enter.
Disable with --disable-named-commands. This option is
disabled by default.
-i, --ignore-spaces Ignore space after function names.
--init-command=name SQL Command to execute when connecting to MySQL server.
Will automatically be re-executed when reconnecting.
--local-infile Enable/disable LOAD DATA LOCAL INFILE.
-b, --no-beep Turn off beep on error.
-h, --host=name Connect to host.
-H, --html Produce HTML output.
-X, --xml Produce XML output.
--line-numbers Write line numbers for errors.
(Defaults to on; use --skip-line-numbers to disable.)
-L, --skip-line-numbers
Don't write line number for errors.
-n, --unbuffered Flush buffer after each query.
--column-names Write column names in results.
(Defaults to on; use --skip-column-names to disable.)
-N, --skip-column-names
Don't write column names in results.
--sigint-ignore Ignore SIGINT (CTRL-C).
-o, --one-databaseIgnore statements except those that occur while the
default database is the one named at the command line.
--pager[=name] Pager to use to display results. If you don't supply an
option, the default pager is taken from your ENV variable
PAGER. Valid pagers are less, more, cat [> filename],
etc. See interactive help (\h) also. This option does not
work in batch mode. Disable with --disable-pager. This
option is disabled by default.
-p, --password[=name]
Password to use when connecting to server. If password is
not given it's asked from the tty.
-P, --port=# Port number to use for connection or 0 for default to, in
order of preference, my.cnf, $MYSQL_TCP_PORT,
/etc/services, built-in default (3306).
--prompt=name Set the mysql prompt to this value.
--protocol=name The protocol to use for connection (tcp, socket, pipe,
memory).
-q, --quick Don't cache result, print it row by row. This may slow
down the server if the output is suspended. Doesn't use
history file.
-r, --raw Write fields without conversion. Used with --batch.
--reconnect Reconnect if the connection is lost. Disable with
--disable-reconnect. This option is enabled by default.
(Defaults to on; use --skip-reconnect to disable.)
-s, --silent Be more silent. Print results with a tab as separator,
each row on new line.
-S, --socket=name The socket file to use for connection.
--server-public-key-path=name
File path to the server public RSA key in PEM format.
--get-server-public-key
Get server public key
--ssl-mode=name SSL connection mode.
--ssl-ca=name CA file in PEM format.
--ssl-capath=name CA directory.
--ssl-cert=name X509 cert in PEM format.
--ssl-cipher=name SSL cipher to use.
--ssl-key=name X509 key in PEM format.
--ssl-crl=name Certificate revocation list.
--ssl-crlpath=nameCertificate revocation list path.
--tls-version=nameTLS version to use, permitted values are: TLSv1, TLSv1.1,
TLSv1.2, TLSv1.3
--ssl-fips-mode=name
SSL FIPS mode (applies only for OpenSSL); permitted
values are: OFF, ON, STRICT
--tls-ciphersuites=name
TLS v1.3 cipher to use.
-t, --table Output in table format.
--tee=name Append everything into outfile. See interactive help (\h)
also. Does not work in batch mode. Disable with
--disable-tee. This option is disabled by default.
-u, --user=name User for login if not current user.
-U, --safe-updatesOnly allow UPDATE and DELETE that uses keys.
-U, --i-am-a-dummySynonym for option --safe-updates, -U.
-v, --verbose Write more. (-v -v -v gives the table output format).
-V, --version Output version information and exit.
-w, --wait Wait and retry if connection is down.
--connect-timeout=# Number of seconds before connection timeout.
--max-allowed-packet=#
The maximum packet length to send to or receive from
server.
--net-buffer-length=#
The buffer size for TCP/IP and socket communication.
--select-limit=# Automatic limit for SELECT when using --safe-updates.
--max-join-size=# Automatic limit for rows in a join when using
--safe-updates.
--show-warnings Show warnings after every statement.
-j, --syslog Log filtered interactive commands to syslog. Filtering of
commands depends on the patterns supplied via histignore
option besides the default patterns.
--plugin-dir=name Directory for client-side plugins.
--default-auth=name Default authentication client-side plugin to use.
--binary-mode By default, ASCII '\0' is disallowed and '\r\n' is
translated to '\n'. This switch turns off both features,
and also turns off parsing of all clientcommands except
\C and DELIMITER, in non-interactive mode (for input
piped to mysql or loaded using the 'source' command).
This is necessary when processing output from mysqlbinlog
that may contain blobs.
--connect-expired-password
Notify the server that this client is prepared to handle
expired password sandbox mode.
--compression-algorithms=name
Use compression algorithm in server/client protocol.
Valid values are any combination of
'zstd','zlib','uncompressed'.
--zstd-compression-level=#
Use this compression level in the client/server protocol,
in case --compression-algorithms=zstd. Valid range is
between 1 and 22, inclusive. Default is 3.
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/local/mysql/etc/my.cnf ~/.my.cnf
The following groups are read: mysql client
The following options may be given as the first argument:
--print-defaults Print the program argument list and exit.
--no-defaults Don't read default options from any option file,
except for login file.
--defaults-file=# Only read default options from the given file #.
--defaults-extra-file=# Read this file after the global files are read.
--defaults-group-suffix=#
Also read groups with concat(group, suffix)
--login-path=# Read this path from the login file.
Variables (--variable-name=value)
and boolean options {FALSE|TRUE}Value (after reading options)
--------------------------------- ----------------------------------------
auto-rehash TRUE
auto-vertical-output FALSE
bind-address (No default value)
binary-as-hex FALSE
character-sets-dir (No default value)
column-type-info FALSE
comments FALSE
compress FALSE
database (No default value)
default-character-set auto
delimiter ;
enable-cleartext-plugin FALSE
vertical FALSE
force FALSE
histignore (No default value)
named-commands FALSE
ignore-spaces FALSE
init-command (No default value)
local-infile TRUE
no-beep FALSE
host (No default value)
html FALSE
xml FALSE
line-numbers TRUE
unbuffered FALSE
column-names TRUE
sigint-ignore FALSE
port 0
prompt mysql>
quick FALSE
raw FALSE
reconnect TRUE
socket (No default value)
server-public-key-path (No default value)
get-server-public-key FALSE
ssl-ca (No default value)
ssl-capath (No default value)
ssl-cert (No default value)
ssl-cipher (No default value)
ssl-key (No default value)
ssl-crl (No default value)
ssl-crlpath (No default value)
tls-version (No default value)
tls-ciphersuites (No default value)
table FALSE
user (No default value)
safe-updates FALSE
i-am-a-dummy FALSE
connect-timeout 0
max-allowed-packet 16777216
net-buffer-length 16384
select-limit 1000
max-join-size 1000000
show-warnings FALSE
plugin-dir (No default value)
default-auth (No default value)
binary-mode FALSE
connect-expired-password FALSE
compression-algorithms (No default value)
zstd-compression-level 3
2.登录后使用帮助
mysql> help
或
mysql> \h
或
mysql> \?
mysql> \?
For information about MySQL products and services, visit:
http://www.mysql.com/
For developer information, including the MySQL Reference Manual, visit:
http://dev.mysql.com/
To buy MySQL Enterprise support, training, or other products, visit:
https://shop.mysql.com/
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 . 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 . 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.
For server side help, type 'help contents'
3.根据上面的帮助，我们可以看到，可以使用 help 被查询的内容
mysql> \? create
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:
CREATE DATABASE
CREATE EVENT
CREATE FUNCTION
CREATE FUNCTION UDF
CREATE INDEX
CREATE LOGFILE GROUP
CREATE PROCEDURE
CREATE RESOURCE GROUP
CREATE ROLE
CREATE SCHEMA
CREATE SERVER
CREATE SPATIAL REFERENCE SYSTEM
CREATE TABLE
CREATE TABLESPACE
CREATE TRIGGER
CREATE USER
CREATE VIEW
SHOW
SHOW CREATE DATABASE
SHOW CREATE EVENT
SHOW CREATE FUNCTION
SHOW CREATE PROCEDURE
SHOW CREATE SCHEMA
SHOW CREATE TABLE
SHOW CREATE USER
SPATIAL INDEXES
4.查询当前连接的数据信息
mysql> \s
--------------
mysqlVer 8.0.19 for linux-glibc2.12 on x86_64 (MySQL Community Server - GPL)
Connection id: 35
Current database: school
Current user: root@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 8.0.19 MySQL Community Server - GPL
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: utf8mb4
Db characterset: utf8mb4
Client characterset: utf8mb4
Conn.characterset: utf8mb4
UNIX socket: /tmp/mysql.sock
Binary data as: Hexadecimal
Uptime: 1 hour 9 min 26 sec
Threads: 2Questions: 138Slow queries: 0Opens: 181Flush tables: 3Open tables: 101Queries per second avg: 0.033
--------------
5.查询具体的帮助
mysql> \? alter table
mysql> help contents
mysql> ? data types
页:
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