Title: MySQL doesn't starts on AMPPS OS X
Tags: mysql;macos;operating-system;webserver
Question: I have I problem with starting mysql using AMPPS. I'm Using OS X Maverics and last version of Ammps. After little system crash and restart I can`t start mysql.
mysql.err
2014-01-22 18:12:41 398 [Note] Plugin 'FEDERATED' is disabled.
2014-01-22 18:12:41 398 [Note] InnoDB: The InnoDB memory heap is disabled
2014-01-22 18:12:41 398 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2014-01-22 18:12:41 398 [Note] InnoDB: Compressed tables use zlib 1.2.3
2014-01-22 18:12:41 398 [Note] InnoDB: Not using CPU crc32 instructions
2014-01-22 18:12:41 398 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2014-01-22 18:12:41 398 [Note] InnoDB: Completed initialization of buffer pool
2014-01-22 18:12:41 398 [Note] InnoDB: Highest supported file format is Barracuda.
2014-01-22 18:12:41 398 [Note] InnoDB: The log sequence numbers 1252002624 and 1252002624 in ibdata files do not match the log sequence number 1252003161 in the ib_logfiles!
2014-01-22 18:12:41 398 [Note] InnoDB: Database was not shutdown normally!
2014-01-22 18:12:41 398 [Note] InnoDB: Starting crash recovery.
2014-01-22 18:12:41 398 [Note] InnoDB: Reading tablespace information from the .ibd files...
2014-01-22 18:12:41 398 [ERROR] InnoDB: Attempted to open a previously opened tablespace. Previous tablespace analytics/backlinks uses space ID: 1 at filepath: ./analytics/backlinks.ibd. Cannot open tablespace mysql/innodb_table_stats which uses space ID: 1 at filepath: ./mysql/innodb_table_stats.ibd
2014-01-22 18:12:41 a08901a8 InnoDB: Operating system error number 2 in a file operation.
InnoDB: The error means the system cannot find the path specified.
InnoDB: If you are installing InnoDB, remember that you must create
InnoDB: directories yourself, InnoDB does not create them.
InnoDB: Error: could not open single-table tablespace file ./mysql/innodb_table_stats.ibd
InnoDB: We do not continue the crash recovery, because the table may become
InnoDB: corrupt if we cannot apply the log records in the InnoDB log to it.
InnoDB: To fix the problem and start mysqld:
InnoDB: 1) If there is a permission problem in the file and mysqld cannot
InnoDB: open the file, you should modify the permissions.
InnoDB: 2) If the table is not needed, or you can restore it from a backup,
InnoDB: then you can remove the .ibd file, and InnoDB will do a normal
InnoDB: crash recovery and ignore that table.
InnoDB: 3) If the file system or the disk is broken, and you cannot remove
InnoDB: the .ibd file, you can set innodb_force_recovery &gt; 0 in my.cnf
InnoDB: and force InnoDB to continue crash recovery here.
Help me please. I have very important files in DB.

Here is the accepted answer: Solve!
Open AMPPS Application -&gt; MySQL Tab -&gt; Configuration.
In [mysqld] section, add the following line:
innodb_force_recovery = 1
Save the file and try starting MySQL
Remove that line which you just added and Save.
Comment for this answer: Just to add to Halis's point - a comment is a nice way of doing it - just a single hash in front of the line: #.
Comment for this answer: My mac running `yosemite` randomly froze and then shutdown, when I turned it back on I couldn't turn on `mySQL`. Adding this line to the `Config file` worked like a charm!
Comment for this answer: If this solution is not working, try to restart pc & open ampps as soon as the pc is restarted
Comment for this answer: This also happens on OS X Yosemite after a crash, but these steps will sort it.
Comment for this answer: instead of deleting commending will be better choice since after each update problem occurs again.

Here is another answer: So I was facing a similar issue and what I tried was following:-
find / -name mysql
From the output of above command remove all the search results.Then do following:-
brew uninstall mysql
brew clean
Then reboot your machine once and then install once again using following:-
brew install mysql
P.S: I was getting this error error so I could not take backup of my db but I had not so much important data in DB so I removed it anyways

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