ERR (3): Warning: imagecopymerge() expects parameter 9 to be long, string given in lib/Varien/Image/Adapter/Gd2.php

if you encounter this error just reset the settings for watermark and delete uploaded watermark images (need to be transparent)

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Charts not working (1.8.0)

Recently we came across an issue, where the Magento charts were not showing. After hours of debugging, we tried one method, which fixed it. Here it is, how we solved it.
File: \web\app\design\adminhtml\default\default\template\dashboard\graph.phtml
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<p style="<?php echo $_containerStyle?>"><img src="<?php echo $this-/>getChartUrl(false) ?>” alt="chart" title="chart" /></p>
Just change this part of the ,
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getChartUrl(false) ?>
to
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getChartUrl(true) ?>

Backup and Restore MySQL Database Using mysqldump



backup: # mysqldump -u root -p[root_password] [database_name] > dumpfilename.sql

restore:# mysql -u root -p[root_password] [database_name] < dumpfilename.sql
 
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MySQL command to show list of databases on server

you can use the -e option to execute some queries on the command line, EG, to list databases:

 mysql -e “show databases” -uUSER -pPASSWORD

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