SEO Friendly URL for search keywords

Question

I have a website where you can search for a brands, item, and content inside my web. It was designed with tab for each search type, but I want to make the url when changing the tab user friendly and good for SEO.

Is it better to have a url for search result like this

www.example.com/search/{search_keyword}/{tab}

or

www.example.com/search/{search_keyword}?tab={tab}

or

www.example.com/search/?search={search_keyword}&tab={tab}

where {search_keyword} is the keyword that user input, and {tab} is either brands / item / content, because when I look at facebook, stackoverflow, and some other website, they use query string for their search keyword

Edit

My past url is only www.example.com/search/{search_keyword}, and I just added the tab design recently. Consider that I should go with option 1 from the above option, should I make www.example.com/search/{search_keyword} the default for 1 of the 3 tab, and make the other 2 tab with www.example.com/search/{search_keyword}/{tab} to retain the score for the page, or should I make all the tab url with

www.example.com/search/{search_keyword}/{tab}

and use a permanent redirect from www.example.com/search/{search_keyword} to one of the url tab

Answer 1

The first example is best since query string parameters are generally ignored by search engines.

Anything that can be used to "game" a search engine isn't going to count for much. You could have endless spammy keywords as parameters in a URL without effecting the page content so why would a search engine take any notice of them?

But, much more importantly, it's best because it's easier for real people to use and understand. That's the most important thing. Forget trying to appease search engines and think about your users. They'll appreciate it and, if your content is good, maybe they'll give you a backlink - search engines really like backlinks.