Welcome to TwinDB Table Compare’s documentation!¶
Contents:
TwinDB Table Compare¶
TwinDB Table Compare reads percona.``checksums`` from the master and slave
and shows what records are difference if there are any inconsistencies.
- Free software: Apache Software License 2.0
- Documentation: https://twindb-table-compare.readthedocs.io.
- Blogpost with usage examples: https://twindb.com/pt-table-checksum-show-differences/
Credits¶
This package was created with Cookiecutter and the audreyr/cookiecutter-pypackage project template.
Installation¶
Stable release¶
To install TwinDB Table Compare, run this command in your terminal:
$ pip install twindb_table_compare
This is the preferred method to install TwinDB Table Compare, as it will always install the most recent stable release.
If you don’t have pip installed, this Python installation guide can guide you through the process.
From sources¶
The sources for TwinDB Table Compare can be downloaded from the Github repo.
You can either clone the public repository:
$ git clone git://github.com/twindb/twindb_table_compare
Or download the tarball:
$ curl -OL https://github.com/twindb/twindb_table_compare/tarball/master
Once you have a copy of the source, you can install it with:
$ python setup.py install
Usage¶
TwinDB Table Compare should be used in the command line.
This will show differences in data between slave and its master.
twindb_table_compare slave
where slave is a hostname of a MySQL slave.
[root@master vagrant]# twindb_table_compare --user=dba --password=qwerty 192.168.35.251
2016-09-03 22:48:01,732: INFO: twindb_table_compare.get_inconsistencies():127: Executing: SELECT chunk FROM `percona`.`checksums` WHERE (this_crc<>master_crc OR this_cnt<>master_cnt) AND db='mysql' AND tbl='proxies_priv'
2016-09-03 22:48:01,734: INFO: twindb_table_compare.get_inconsistencies():138: Found 1 inconsistent chunk
2016-09-03 22:48:01,734: INFO: twindb_table_compare.get_inconsistencies():141: # mysql.proxies_priv, chunk 1
2016-09-03 22:48:01,736: INFO: twindb_table_compare.get_inconsistencies():143: # chunk index: None
2016-09-03 22:48:01,736: INFO: twindb_table_compare.get_inconsistencies():215: Executing: SELECT * FROM `mysql`.`proxies_priv` WHERE 1
2016-09-03 22:48:01,743: INFO: twindb_table_compare.get_inconsistencies():257: Differences between slave 192.168.35.251 and its master:
--- /tmp/master.GZ8S7V 2016-09-03 22:48:01.737762174 +0000
+++ /tmp/slave.9t4HhV 2016-09-03 22:48:01.738761674 +0000
@@ -1,2 +1,2 @@
-localhost root 1 2016-09-03 20:02:28
-master.box root 1 2016-09-03 20:02:28
+localhost root 1 2016-09-03 20:10:04
+slave.box root 1 2016-09-03 20:10:04
2016-09-03 22:48:01,746: INFO: twindb_table_compare.get_inconsistencies():127: Executing: SELECT chunk FROM `percona`.`checksums` WHERE (this_crc<>master_crc OR this_cnt<>master_cnt) AND db='mysql' AND tbl='user'
2016-09-03 22:48:01,747: INFO: twindb_table_compare.get_inconsistencies():138: Found 1 inconsistent chunk
2016-09-03 22:48:01,747: INFO: twindb_table_compare.get_inconsistencies():141: # mysql.user, chunk 1
2016-09-03 22:48:01,747: INFO: twindb_table_compare.get_inconsistencies():143: # chunk index: None
2016-09-03 22:48:01,748: INFO: twindb_table_compare.get_inconsistencies():215: Executing: SELECT * FROM `mysql`.`user` WHERE 1
2016-09-03 22:48:01,757: INFO: twindb_table_compare.get_inconsistencies():257: Differences between slave 192.168.35.251 and its master:
--- /tmp/master.l_zYw7 2016-09-03 22:48:01.749756174 +0000
+++ /tmp/slave.39qG9N 2016-09-03 22:48:01.752754674 +0000
@@ -1,9 +1,9 @@
localhost root Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0 mysql_native_password N
-master.box root Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0 mysql_native_password N
+slave.box root Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0 mysql_native_password N
127.0.0.1 root Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0 mysql_native_password N
::1 root Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0 mysql_native_password N
localhost N N N N N N N N N N N N N N N N N N N N N N N N N N N N N 0 0 0 0 mysql_native_password None N
-master.box N N N N N N N N N N N N N N N N N N N N N N N N N N N N N 0 0 0 0 mysql_native_password None N
+slave.box N N N N N N N N N N N N N N N N N N N N N N N N N N N N N 0 0 0 0 mysql_native_password None N
% dba *AA1420F182E88B9E5F874F6FBE7459291E8F4601 Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0 mysql_native_password N
localhost dba *AA1420F182E88B9E5F874F6FBE7459291E8F4601 Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 0 0 0 0mysql_native_password N
% repl *809534247D21AC735802078139D8A854F45C31F3 N N N N N N N N N N N N N N N N N N N Y N N N N N N N N N 0 0 0 0 mysql_native_password N
Run twindb_table_compare --help for other options.
Contributing¶
Contributions are welcome, and they are greatly appreciated! Every little bit helps, and credit will always be given.
You can contribute in many ways:
Types of Contributions¶
Report Bugs¶
Report bugs at https://github.com/twindb/twindb_table_compare/issues.
If you are reporting a bug, please include:
- Your operating system name and version.
- Any details about your local setup that might be helpful in troubleshooting.
- Detailed steps to reproduce the bug.
Fix Bugs¶
Look through the GitHub issues for bugs. Anything tagged with “bug” and “help wanted” is open to whoever wants to implement it.
Implement Features¶
Look through the GitHub issues for features. Anything tagged with “enhancement” and “help wanted” is open to whoever wants to implement it.
Write Documentation¶
TwinDB Table Compare could always use more documentation, whether as part of the official TwinDB Table Compare docs, in docstrings, or even on the web in blog posts, articles, and such.
Submit Feedback¶
The best way to send feedback is to file an issue at https://github.com/twindb/twindb_table_compare/issues.
If you are proposing a feature:
- Explain in detail how it would work.
- Keep the scope as narrow as possible, to make it easier to implement.
- Remember that this is a volunteer-driven project, and that contributions are welcome :)
Get Started!¶
Ready to contribute? Here’s how to set up twindb_table_compare for local development.
Fork the twindb_table_compare repo on GitHub.
Clone your fork locally:
$ git clone git@github.com:your_name_here/twindb_table_compare.git
Install your local copy into a virtualenv. Assuming you have virtualenvwrapper installed, this is how you set up your fork for local development:
$ mkvirtualenv twindb_table_compare $ cd twindb_table_compare/ $ make bootstrapCreate a branch for local development:
$ git checkout -b name-of-your-bugfix-or-feature
Now you can make your changes locally.
5. When you’re done making changes, check that your changes pass lenter and
the tests, including testing other Python versions with tox:
$ make lint
$ make test-all
To get flake8 and tox, just pip install them into your virtualenv.
Commit your changes and push your branch to GitHub:
$ git add . $ git commit -m "Your detailed description of your changes." $ git push origin name-of-your-bugfix-or-featureSubmit a pull request through the GitHub website.
Pull Request Guidelines¶
Before you submit a pull request, check that it meets these guidelines:
- The pull request should include tests.
- If the pull request adds functionality, the docs should be updated. Put your new functionality into a function with a docstring, and add the feature to the list in README.rst.
- The pull request should work for Python 2.6, 2.7, and for PyPy. Check https://travis-ci.org/twindb/twindb_table_compare/pull_requests and make sure that the tests pass for all supported Python versions.
Tips¶
To run a subset of tests:
$ py.test tests/unit/test_twindb_table_compare.py
$ py.test tests/unit/test_twindb_table_compare.py::test_build_chunk_query
Credits¶
Development Lead¶
- Aleksandr Kuzminsky <aleks@twindb.com>
Contributors¶
None yet. Why not be the first?