How to get option values set from all sites within a Multisite setup?

You can use get_site_option() function to get single network-wide option.

Example :

$singleoption = get_site_option( 'siteurl' );

If you want to get all options from all sites use wp_load_alloptions() function.

Example :

$alloptions = wp_load_alloptions()

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)