To export tables from a DB we can use
mysqldump tool which is available
on hosts with installed MySQL DB. This means we can also run it in MySQL
Docker container:
$ docker run mysql /usr/bin/mysqldump
Usage: mysqldump [OPTIONS] database [tables]
OR mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
OR mysqldump [OPTIONS] --all-databases [OPTIONS]
For more options, use mysqldump --help
To check mysqldump version:
$ docker run mysql /usr/bin/mysqldump --version
mysqldump Ver 8.0.27 for Linux on x86_64 (MySQL Community Server - GPL)
Help Output
$ docker run mysql /usr/bin/mysqldump --help
mysqldump Ver 8.0.27 for Linux on x86_64 (MySQL Community Server - GPL)
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Dumping structure and contents of MySQL databases and tables.
Usage: mysqldump [OPTIONS] database [tables]
OR mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
OR mysqldump [OPTIONS] --all-databases [OPTIONS]
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf ~/.my.cnf
The following groups are read: mysqldump 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.
-A, --all-databases Dump all the databases. This will be same as --databases
with all databases selected.
-Y, --all-tablespaces
Dump all the tablespaces.
-y, --no-tablespaces
Do not dump any tablespace information.
--add-drop-database Add a DROP DATABASE before each create.
--add-drop-table Add a DROP TABLE before each create.
(Defaults to on; use --skip-add-drop-table to disable.)
--add-drop-trigger Add a DROP TRIGGER before each create.
--add-locks Add locks around INSERT statements.
(Defaults to on; use --skip-add-locks to disable.)
--allow-keywords Allow creation of column names that are keywords.
--apply-replica-statements
Adds 'STOP SLAVE' prior to 'CHANGE MASTER' and 'START
SLAVE' to bottom of dump.
--apply-slave-statements
This option is deprecated and will be removed in a future
version. Use apply-replica-statements instead.
--bind-address=name IP address to bind to.
--character-sets-dir=name
Directory for character set files.
--column-statistics Add an ANALYZE TABLE statement to regenerate any existing
column statistics.
(Defaults to on; use --skip-column-statistics to disable.)
-i, --comments Write additional information.
(Defaults to on; use --skip-comments to disable.)
--compatible=name Change the dump to be compatible with a given mode. By
default tables are dumped in a format optimized for
MySQL. The only legal mode is ANSI.Note: Requires MySQL
server version 4.1.0 or higher. This option is ignored
with earlier server versions.
--compact Give less verbose output (useful for debugging). Disables
structure comments and header/footer constructs. Enables
options --skip-add-drop-table --skip-add-locks
--skip-comments --skip-disable-keys --skip-set-charset.
-c, --complete-insert
Use complete insert statements.
-C, --compress Use compression in server/client protocol.
-a, --create-options
Include all MySQL specific create options.
(Defaults to on; use --skip-create-options to disable.)
-B, --databases Dump several databases. Note the difference in usage; in
this case no tables are given. All name arguments are
regarded as database names. 'USE db_name;' will be
included in the output.
-#, --debug[=#] This is a non-debug version. Catch this and exit.
--debug-check This is a non-debug version. Catch this and exit.
--debug-info This is a non-debug version. Catch this and exit.
--default-character-set=name
Set the default character set.
--delete-source-logs
Rotate logs before the backup, equivalent to FLUSH LOGS,
and purge all old binary logs after the backup,
equivalent to PURGE LOGS. This automatically enables
--source-data.
--delete-master-logs
This option is deprecated and will be removed in a future
version. Use delete-source-logs instead.
-K, --disable-keys '/*!40000 ALTER TABLE tb_name DISABLE KEYS */; and
'/*!40000 ALTER TABLE tb_name ENABLE KEYS */; will be put
in the output.
(Defaults to on; use --skip-disable-keys to disable.)
--dump-replica[=#] This causes the binary log position and filename of the
source to be appended to the dumped data output. Setting
the value to 1, will printit as a CHANGE MASTER command
in the dumped data output; if equal to 2, that command
will be prefixed with a comment symbol. This option will
turn --lock-all-tables on, unless --single-transaction is
specified too (in which case a global read lock is only
taken a short time at the beginning of the dump - don't
forget to read about --single-transaction below). In all
cases any action on logs will happen at the exact moment
of the dump.Option automatically turns --lock-tables off.
--dump-slave[=#] This option is deprecated and will be removed in a future
version. Use dump-replica instead.
-E, --events Dump events.
-e, --extended-insert
Use multiple-row INSERT syntax that include several
VALUES lists.
(Defaults to on; use --skip-extended-insert to disable.)
--fields-terminated-by=name
Fields in the output file are terminated by the given
string.
--fields-enclosed-by=name
Fields in the output file are enclosed by the given
character.
--fields-optionally-enclosed-by=name
Fields in the output file are optionally enclosed by the
given character.
--fields-escaped-by=name
Fields in the output file are escaped by the given
character.
-F, --flush-logs Flush logs file in server before starting dump. Note that
if you dump many databases at once (using the option
--databases= or --all-databases), the logs will be
flushed for each database dumped. The exception is when
using --lock-all-tables or --source-data: in this case
the logs will be flushed only once, corresponding to the
moment all tables are locked. So if you want your dump
and the log flush to happen at the same exact moment you
should use --lock-all-tables or --source-data with
--flush-logs.
--flush-privileges Emit a FLUSH PRIVILEGES statement after dumping the mysql
database. This option should be used any time the dump
contains the mysql database and any other database that
depends on the data in the mysql database for proper
restore.
-f, --force Continue even if we get an SQL error.
-?, --help Display this help message and exit.
--hex-blob Dump binary strings (BINARY, VARBINARY, BLOB) in
hexadecimal format.
-h, --host=name Connect to host.
--ignore-error=name A comma-separated list of error numbers to be ignored if
encountered during dump.
--ignore-table=name Do not dump the specified table. To specify more than one
table to ignore, use the directive multiple times, once
for each table. Each table must be specified with both
database and table names, e.g.,
--ignore-table=database.table.
--include-source-host-port
Adds 'MASTER_HOST=<host>, MASTER_PORT=<port>' to 'CHANGE
MASTER TO..' in dump produced with --dump-replica.
--include-master-host-port
This option is deprecated and will be removed in a future
version. Use include-source-host-port instead.
--insert-ignore Insert rows with INSERT IGNORE.
--lines-terminated-by=name
Lines in the output file are terminated by the given
string.
-x, --lock-all-tables
Locks all tables across all databases. This is achieved
by taking a global read lock for the duration of the
whole dump. Automatically turns --single-transaction and
--lock-tables off.
-l, --lock-tables Lock all tables for read.
(Defaults to on; use --skip-lock-tables to disable.)
--log-error=name Append warnings and errors to given file.
--source-data[=#] This causes the binary log position and filename to be
appended to the output. If equal to 1, will print it as a
CHANGE MASTER command; if equal to 2, that command will
be prefixed with a comment symbol. This option will turn
--lock-all-tables on, unless --single-transaction is
specified too (in which case a global read lock is only
taken a short time at the beginning of the dump; don't
forget to read about --single-transaction below). In all
cases, any action on logs will happen at the exact moment
of the dump. Option automatically turns --lock-tables
off.
--master-data[=#] This option is deprecated and will be removed in a future
version. Use source-data instead.
--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.
--no-autocommit Wrap tables with autocommit/commit statements.
-n, --no-create-db Suppress the CREATE DATABASE ... IF EXISTS statement that
normally is output for each dumped database if
--all-databases or --databases is given.
-t, --no-create-info
Don't write table creation info.
-d, --no-data No row information.
-N, --no-set-names Same as --skip-set-charset.
--opt Same as --add-drop-table, --add-locks, --create-options,
--quick, --extended-insert, --lock-tables, --set-charset,
and --disable-keys. Enabled by default, disable with
--skip-opt.
--order-by-primary Sorts each table's rows by primary key, or first unique
key, if such a key exists. Useful when dumping a MyISAM
table to be loaded into an InnoDB table, but will make
the dump itself take considerably longer.
-p, --password[=name]
Password to use when connecting to server. If password is
not given it's asked from the tty.
-,, --password1[=name]
Password for first factor authentication plugin.
-,, --password2[=name]
Password for second factor authentication plugin.
-,, --password3[=name]
Password for third factor authentication plugin.
-P, --port=# Port number to use for connection.
--protocol=name The protocol to use for connection (tcp, socket, pipe,
memory).
-q, --quick Don't buffer query, dump directly to stdout.
(Defaults to on; use --skip-quick to disable.)
-Q, --quote-names Quote table and column names with backticks (`).
(Defaults to on; use --skip-quote-names to disable.)
--replace Use REPLACE INTO instead of INSERT INTO.
-r, --result-file=name
Direct output to a given file. This option should be used
in systems (e.g., DOS, Windows) that use carriage-return
linefeed pairs (\r\n) to separate text lines. This option
ensures that only a single newline is used.
-R, --routines Dump stored routines (functions and procedures).
--set-charset Add 'SET NAMES default_character_set' to the output.
(Defaults to on; use --skip-set-charset to disable.)
--set-gtid-purged[=name]
Add 'SET @@GLOBAL.GTID_PURGED' to the output. Possible
values for this option are ON, COMMENTED, OFF and AUTO.
If ON is used and GTIDs are not enabled on the server, an
error is generated. If COMMENTED is used, 'SET
@@GLOBAL.GTID_PURGED' is added as a comment. If OFF is
used, this option does nothing. If AUTO is used and GTIDs
are enabled on the server, 'SET @@GLOBAL.GTID_PURGED' is
added to the output. If GTIDs are disabled, AUTO does
nothing. If no value is supplied then the default (AUTO)
value will be considered.
--single-transaction
Creates a consistent snapshot by dumping all tables in a
single transaction. Works ONLY for tables stored in
storage engines which support multiversioning (currently
only InnoDB does); the dump is NOT guaranteed to be
consistent for other storage engines. While a
--single-transaction dump is in process, to ensure a
valid dump file (correct table contents and binary log
position), no other connection should use the following
statements: ALTER TABLE, DROP TABLE, RENAME TABLE,
TRUNCATE TABLE, as consistent snapshot is not isolated
from them. Option automatically turns off --lock-tables.
--dump-date Put a dump date to the end of the output.
(Defaults to on; use --skip-dump-date to disable.)
--skip-opt Disable --opt. Disables --add-drop-table, --add-locks,
--create-options, --quick, --extended-insert,
--lock-tables, --set-charset, and --disable-keys.
-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=name Certificate revocation list path.
--tls-version=name TLS 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, --tab=name Create tab-separated textfile for each table to given
path. (Create .sql and .txt files.) NOTE: This only works
if mysqldump is run on the same machine as the mysqld
server.
--tables Overrides option --databases (-B).
--triggers Dump triggers for each dumped table.
(Defaults to on; use --skip-triggers to disable.)
--tz-utc SET TIME_ZONE='+00:00' at top of dump to allow dumping of
TIMESTAMP data when a server has data in different time
zones or data is being moved between servers with
different time zones.
(Defaults to on; use --skip-tz-utc to disable.)
-u, --user=name User for login if not current user.
-v, --verbose Print info about the various stages.
-V, --version Output version information and exit.
-w, --where=name Dump only selected records. Quotes are mandatory.
-X, --xml Dump a database as well formed XML.
--plugin-dir=name Directory for client-side plugins.
--default-auth=name Default authentication client-side plugin to use.
--enable-cleartext-plugin
Enable/disable the clear text authentication plugin.
-M, --network-timeout
Allows huge tables to be dumped by setting
max_allowed_packet to maximum value and
net_read_timeout/net_write_timeout to large value.
(Defaults to on; use --skip-network-timeout to disable.)
--show-create-table-skip-secondary-engine
Controls whether SECONDARY_ENGINE CREATE TABLE clause
should be dumped or not. No effect on older servers that
do not support the server side option.
--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.
Variables (--variable-name=value)
and boolean options {FALSE|TRUE} Value (after reading options)
--------------------------------------- ----------------------------------
all-databases FALSE
all-tablespaces FALSE
no-tablespaces FALSE
add-drop-database FALSE
add-drop-table TRUE
add-drop-trigger FALSE
add-locks TRUE
allow-keywords FALSE
apply-replica-statements FALSE
apply-slave-statements FALSE
bind-address (No default value)
character-sets-dir (No default value)
column-statistics TRUE
comments TRUE
compatible (No default value)
compact FALSE
complete-insert FALSE
compress FALSE
create-options TRUE
databases FALSE
default-character-set utf8mb4
delete-source-logs FALSE
delete-master-logs FALSE
disable-keys TRUE
dump-replica 0
dump-slave 0
events FALSE
extended-insert TRUE
fields-terminated-by (No default value)
fields-enclosed-by (No default value)
fields-optionally-enclosed-by (No default value)
fields-escaped-by (No default value)
flush-logs FALSE
flush-privileges FALSE
force FALSE
hex-blob FALSE
host (No default value)
ignore-error (No default value)
include-source-host-port FALSE
include-master-host-port FALSE
insert-ignore FALSE
lines-terminated-by (No default value)
lock-all-tables FALSE
lock-tables TRUE
log-error (No default value)
source-data 0
master-data 0
max-allowed-packet 25165824
net-buffer-length 1046528
no-autocommit FALSE
no-create-db FALSE
no-create-info FALSE
no-data FALSE
order-by-primary FALSE
port 0
quick TRUE
quote-names TRUE
replace FALSE
routines FALSE
set-charset TRUE
single-transaction FALSE
dump-date 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)
tab (No default value)
triggers TRUE
tz-utc TRUE
user (No default value)
verbose FALSE
where (No default value)
plugin-dir (No default value)
default-auth (No default value)
enable-cleartext-plugin FALSE
network-timeout TRUE
show-create-table-skip-secondary-engine FALSE
compression-algorithms (No default value)
zstd-compression-level 3
This bash script snippet contains an example how to run mysqldump in a Docker contianer and make it connect to a DB and export tables my_table_01 and my_table_02 from schema my_db:
db_endpoint_address=127.0.0.1
db_endpoint_port=3306
db_user=myuser
db_pass=mypass
timestamp=$(date +%Y%m%d_%H%M%S)
dump_file_name=dump_$timestamp.sql
docker run \
-it \
mysql \
/usr/bin/mysqldump \
--host=$db_endpoint_address \
--port=$db_endpoint_port \
--user=$db_user \
--password=$db_pass \
my_db my_table_01 my_table_02 > $dump_file_name
The command above pipes entire mysqldump output into a file, including a warning and error messages. In the case above, we're passing password to a MySQL client application via command line which is not secure so mysqldump outputs a warning which ends up at the beginning of the dump file:
$ head -20 dump_20220208_103008.sql
mysqldump: [Warning] Using a password on the command line interface can be insecure.
-- MySQL dump 10.13 Distrib 8.0.27, for Linux (x86_64)
--
-- Host: my-mysql-db.uskh3hyrsza4.us-east-1.rds.amazonaws.com Database: my_db
-- ------------------------------------------------------
-- Server version 8.0.17
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!50503 SET NAMES utf8mb4 */;
...
If we try to import this file into another instance of MySQL, DB server will reset the connection:
$ cat dump_20220208_103008.sql | docker run -i mysql /usr/bin/mysql --host=172.17.0.2 --port=3306 --user=root --password=root
mysql: [Warning] Using a password on the command line interface can be insecure.
ERROR 1064 (42000) at line 1: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'mysqldump: [Warning] Using a password on the command line interface can be insec' at line 1
read unix @->/run/docker.sock: read: connection reset by peer
To prevent this we can manually remove the warning from a dump sql file or, better, use recommended way of passing credentials:
Dump files contain SQL commands for creating views. This can be easily verified by inspecting the content of the dump file:
$ cat Dump20220208-local-db.sql | grep VIEW
/*!50001 DROP VIEW IF EXISTS `my_view_01`*/;
/*!50001 CREATE VIEW `my_view_01` AS SELECT
/*!50001 DROP VIEW IF EXISTS `my_view_02`*/;
/*!50001 CREATE VIEW `my_view_02` AS SELEC
Locally Installed mysqldump
To check if mysqldump is installed locally:
$ mysqldump
Usage: mysqldump [OPTIONS] database [tables]
OR mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
OR mysqldump [OPTIONS] --all-databases [OPTIONS]
For more options, use mysqldump --help
To find its path:
$ which mysqldump
/usr/bin/mysqldump
Instead of passing credentials via command line (which might be insecure as they could be found in command line history) we can create a (temporary) file in home directory:
$ touch ~/.my.cnf
$ ls -la ~/.my.cnf
-rw-rw-r-- 1 bojan bojan 0 Sep 27 11:23 /home/bojan/.my.cnf
..and leave credentials there in form:
[mysqldump]
user=<db_username>
password=<db_password>
To export all databases:
$ mysqldump \
--host=my-db.ukkh6hyrsza3.us-east-1.rds.amazonaws.com \
--port=3306 \
--all-databases \
> my-db-dump.sql
Warning: A partial dump from a server that has GTIDs will by default include the GTIDs of all transactions, even those that changed suppressed parts of the database. If you don't want to restore GTIDs, pass --set-gtid-purged=OFF. To make a complete dump, pass --all-databases --triggers --routines --events.
cnf file can have an arbitrary name and be saved at arbitrary location in which case we need to specify it via this command line argument:
--defaults-file=my_other.cnf
Importing dump file
To import databases (schemas) into an empty database:
$ mysql \
--user=my_local_db_user \
--password=my_local_db_pass \
--host=0.0.0.0 \
--port=3306 \
< my-db-dump.sql
mysql: [Warning] Using a password on the command line interface can be insecure.
If import fails with error:
ERROR 1465 (HY000) at line 1125: Triggers can not be created on system tables
...then delete the dump file and execute export command but with this additional argument:
--skip-triggers
---
