Provided by: percona-toolkit_3.2.1-1_all 
NAME
pt-fk-error-logger - Log MySQL foreign key errors.
SYNOPSIS
Usage: pt-fk-error-logger [OPTIONS] [DSN]
pt-fk-error-logger logs information about foreign key errors on the given DSN. Information is printed to
"STDOUT", and it can also be saved to a table by specifying "--dest". The tool runs for forever unless
"--run-time" or "--iterations" is specified.
Print foreign key errors on host1:
pt-fk-error-logger h=host1
Print foreign key errors on host1 once then exit:
pt-fk-error-logger h=host1 --iterations 1
Save foreign key errors on host1 to percona_schema.fke on host2:
pt-fk-error-logger h=host1 --dest h=host2,D=percona_schema,t=fke
RISKS
Percona Toolkit is mature, proven in the real world, and well tested, but all database tools can pose a
risk to the system and the database server. Before using this tool, please:
• Read the tool's documentation
• Review the tool's known "BUGS"
• Test the tool on a non-production server
• Backup your production server and verify the backups
DESCRIPTION
pt-fk-error-logger prints or saves the foreign key errors text from "SHOW INNODB STATUS". The errors are
not parsed or interpreted in any way. Foreign key errors are uniquely identified by their timestamp.
Only new (more recent) errors are printed or saved.
By default the tool runs forever, checking every "--interval" seconds for new foreign key errors.
Specify "--run-time" and/or "--iterations" to limit how long the tool runs.
OUTPUT
The foreign key error text from "SHOW ENGINE INNODB STATUS" is printed to "STDOUT", unless "--quiet" is
specified. Errors and warnings are printed to "STDERR".
OPTIONS
This tool accepts additional command-line arguments. Refer to the "SYNOPSIS" and usage information for
details.
--ask-pass
Prompt for a password when connecting to MySQL.
--charset
short form: -A; type: string
Default character set. If the value is utf8, sets Perl's binmode on STDOUT to utf8, passes the
mysql_enable_utf8 option to DBD::mysql, and runs SET NAMES UTF8 after connecting to MySQL. Any other
value sets binmode on STDOUT without the utf8 layer, and runs SET NAMES after connecting to MySQL.
--config
type: Array
Read this comma-separated list of config files; if specified, this must be the first option on the
command line.
--daemonize
Fork to the background and detach from the shell. POSIX operating systems only.
--database
short form: -D; type: string
Connect to this database.
--defaults-file
short form: -F; type: string
Only read mysql options from the given file. You must give an absolute pathname.
--dest
type: DSN
Save foreign key errors in this table. The DSN must specify a database (D) and table (t).
Missing DSN values are inherited from the DSN being monitored, so you can omit most values if you're
saving foreign key errors on the same host.
The following table is suggested:
CREATE TABLE foreign_key_errors (
ts datetime NOT NULL,
error text NOT NULL,
PRIMARY KEY (ts)
)
The only information saved is the timestamp and the foreign key error text.
--help
Show help and exit.
--host
short form: -h; type: string
Connect to host.
--interval
type: time; default: 30
How often to check for foreign key errors.
--iterations
type: int
How many times to check for foreign key errors. By default, this option is undefined which means an
infinite number of iterations. The tool always exits for "--run-time", regardless of the value
specified for this option. For example, the tool will exit after 1 minute with "--run-time 1m
--iterations 4 --interval 30" because 4 iterations at 30 second intervals would take 2 minutes,
longer than the 1 mintue run-time.
--log
type: string
Print all output to this file when daemonized.
--password
short form: -p; type: string
Password to use when connecting. If password contains commas they must be escaped with a backslash:
"exam\,ple"
--pid
type: string
Create the given PID file. The tool won't start if the PID file already exists and the PID it
contains is different than the current PID. However, if the PID file exists and the PID it contains
is no longer running, the tool will overwrite the PID file with the current PID. The PID file is
removed automatically when the tool exits.
--port
short form: -P; type: int
Port number to use for connection.
--quiet
Do not print foreign key errors; only print errors and warnings to "STDERR".
--run-time
type: time
How long to run before exiting. By default, the tool runs forever.
--set-vars
type: Array
Set the MySQL variables in this comma-separated list of "variable=value" pairs.
By default, the tool sets:
wait_timeout=10000
Variables specified on the command line override these defaults. For example, specifying "--set-vars
wait_timeout=500" overrides the defaultvalue of 10000.
The tool prints a warning and continues if a variable cannot be set.
--socket
short form: -S; type: string
Socket file to use for connection.
--user
short form: -u; type: string
User for login if not current user.
--version
Show version and exit.
--[no]version-check
default: yes
Check for the latest version of Percona Toolkit, MySQL, and other programs.
This is a standard "check for updates automatically" feature, with two additional features. First,
the tool checks its own version and also the versions of the following software: operating system,
Percona Monitoring and Management (PMM), MySQL, Perl, MySQL driver for Perl (DBD::mysql), and Percona
Toolkit. Second, it checks for and warns about versions with known problems. For example, MySQL
5.5.25 had a critical bug and was re-released as 5.5.25a.
A secure connection to Percona’s Version Check database server is done to perform these checks. Each
request is logged by the server, including software version numbers and unique ID of the checked
system. The ID is generated by the Percona Toolkit installation script or when the Version Check
database call is done for the first time.
Any updates or known problems are printed to STDOUT before the tool's normal output. This feature
should never interfere with the normal operation of the tool.
For more information, visit <https://www.percona.com/doc/percona-toolkit/LATEST/version-check.html>.
DSN OPTIONS
These DSN options are used to create a DSN. Each option is given like "option=value". The options are
case-sensitive, so P and p are not the same option. There cannot be whitespace before or after the "="
and if the value contains whitespace it must be quoted. DSN options are comma-separated. See the
percona-toolkit manpage for full details.
• A
dsn: charset; copy: yes
Default character set.
• D
dsn: database; copy: yes
Default database.
• F
dsn: mysql_read_default_file; copy: yes
Only read default options from the given file
• h
dsn: host; copy: yes
Connect to host.
• p
dsn: password; copy: yes
Password to use when connecting. If password contains commas they must be escaped with a backslash:
"exam\,ple"
• P
dsn: port; copy: yes
Port number to use for connection.
• S
dsn: mysql_socket; copy: yes
Socket file to use for connection.
• t
Table in which to store foreign key errors.
• u
dsn: user; copy: yes
User for login if not current user.
ENVIRONMENT
The environment variable "PTDEBUG" enables verbose debugging output to STDERR. To enable debugging and
capture all output to a file, run the tool like:
PTDEBUG=1 pt-fk-error-logger ... > FILE 2>&1
Be careful: debugging output is voluminous and can generate several megabytes of output.
SYSTEM REQUIREMENTS
You need Perl, DBI, DBD::mysql, and some core packages that ought to be installed in any reasonably new
version of Perl.
BUGS
For a list of known bugs, see <http://www.percona.com/bugs/pt-fk-error-logger>.
Please report bugs at <https://jira.percona.com/projects/PT>. Include the following information in your
bug report:
• Complete command-line used to run the tool
• Tool "--version"
• MySQL version of all servers involved
• Output from the tool including STDERR
• Input files (log/dump/config files, etc.)
If possible, include debugging output by running the tool with "PTDEBUG"; see "ENVIRONMENT".
DOWNLOADING
Visit <http://www.percona.com/software/percona-toolkit/> to download the latest release of Percona
Toolkit. Or, get the latest release from the command line:
wget percona.com/get/percona-toolkit.tar.gz
wget percona.com/get/percona-toolkit.rpm
wget percona.com/get/percona-toolkit.deb
You can also get individual tools from the latest release:
wget percona.com/get/TOOL
Replace "TOOL" with the name of any tool.
AUTHORS
Daniel Nichter
ABOUT PERCONA TOOLKIT
This tool is part of Percona Toolkit, a collection of advanced command-line tools for MySQL developed by
Percona. Percona Toolkit was forked from two projects in June, 2011: Maatkit and Aspersa. Those
projects were created by Baron Schwartz and primarily developed by him and Daniel Nichter. Visit
<http://www.percona.com/software/> to learn about other free, open-source software from Percona.
COPYRIGHT, LICENSE, AND WARRANTY
This program is copyright 2011-2018 Percona LLC and/or its affiliates.
THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU
General Public License as published by the Free Software Foundation, version 2; OR the Perl Artistic
License. On UNIX and similar systems, you can issue `man perlgpl' or `man perlartistic' to read these
licenses.
You should have received a copy of the GNU General Public License along with this program; if not, write
to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
VERSION
pt-fk-error-logger 3.2.1
POD ERRORS
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Around line 4522:
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perl v5.30.3 2020-08-30 PT-FK-ERROR-LOGGER(1p)