Wordpress

If you want to embed php in Wordpress, you will want to install the Exec php plugin.

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This likely happened due to you renaming the wp_ prefix to something else to prevent SQL injection attacks. If so, there is one last mysql command you should run on your database (after doing a backup).

UPDATE `newprefix_usermeta` SET `meta_key` = REPLACE( `meta_key`, 'wp_', 'newprefix_' );

UPDATE `newprefix_options` SET `option_name` = 'newprefix_user_roles' WHERE `option_name` ='wp_user_roles' AND `blog_id` =0;

Replace newprefix with your new prefix.