If you have PHP knowledge then its very easy to handle the various mistakes occurred in any website very easily.
Hi friend, PHP knowledge will be helpful while verifying markup (html/xhtml) of web documents using W3C validations tool, handling page not found error and redirecting to home or index page of website. ============ Abhishek
running php on a linux server the URL canonicalization process is handled by the htaccess file, not php.
it will not actually help you in the SEO. but you will get enough help when you will fell into any problem regarding your site's design or this type. so its important.
If you put information from MySQL and PHP scripts DIRECTLY in yout HTML documents....SEO may be affected. The keyword is MAY. It depends on what the information is. Usually crawlers read meta information in your header, links, tags and text in your pages. If you put MySQL and PHP into the body of your page, the crawlers may read it as text. If you link to external PHP documents which call on the MySQL database, and you protect the PHP with .htaccess no search engine robot will access them.
You won't have a huge edge by knowing PHP, but it should be able to help you build a more precise and SEO specific website.
I think for doing professional SEO you need not to know php. There have not any great issue of SEO which requires php. Without knowing php you will be able to do perfect SEo of your site and be a successful online marketing expert.
hi Guisbar, you have posted an excellent explanation for the topic. but i would like to add few points more. if a website is developed using php then the owner of the website gets a dynamic website where he can place fresh content everyday and he will not have to worry about the internal linking of the pages which will be done automatically like in wordpress. but if a caching system is used along with apache web-server like (varnish) then the search engine crawlers can easily get the html pages which will lead to a better performance. what do you say ? another thing i would like to comment on is that raw php code can't be displayed as the web-server converts it into html & sends it to the browser. in that case what the browser receives the search engine robots receives the similar content.
PHP start from HTML which is very useful in SEO. Moreover you can closely check the structure of website and make suggestion as SEO point of view.