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Native table 'performance_schema'. 'file_instances' has the wrong structure

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I am getting the following:

Native table 'performance_schema'.'file_instances' has the wrong structure
Native table 'performance_schema'.'rwlock_instances' has the wrong structure
Native table 'performance_schema'.'mutex_instances' has the wrong structure

The problem appears if you have inconsistant data or you have upgraded MySQL


Backup your databases first,


Warning: mysql_select_db(): supplied argument is not a valid MySQL-Link resource in /var/www/html/xy

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mysql_select_db() expects the second parameter to be a resource identifier = your connection.:

function Visit($url)
    $spyware = mysql_connect(); // set this to connect properly
    echo $url;
    mysql_select_db($database_abc, $abc) || die(mysql_error());
    // the rest of your function goes on ...



Upgrading from MySQL 5.1 to 5.5 issues and solution

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It is good practice to back up your data before installing any new version of software. Although MySQL works very hard to ensure a high level of quality, you should protect your data by making a backup.

To upgrade to 5.5 from any previous version, MySQL recommends that you dump your tables with mysqldump before upgrading and reload the dump file after upgrading. Use the --all-databases option to include all databases in the dump. If your databases include stored programs, use the --routines and --events options as well.


MySQL table is marked as crashed and last repair failed

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Go to your data folder and try running

service mysqld stop
myisamchk -r

You should stop MySQL process first.

If that doesn't work, you can try with

myisamchk -r -v -f




How to install BandwidthD in FreeBSD?

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About BandwidthD:

BandwidthD tracks usage of TCP/IP network subnets and builds html files with graphs to display utilization. Charts are built by individual IPs, and by default display utilization over 2 day, 8 day, 40 day, and 400 day periods. Furthermore, each ip address's utilization can be logged out at intervals of 3.3 minutes, 10 minutes, 1 hour or 12 hours in cdf format, or to a backend database server. HTTP, TCP, UDP, ICMP, VPN, and P2P traffic are color coded.


Installing BandwidthD:

Last Updated on Wednesday, 04 September 2013 06:34

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