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It might confuse Google.
A site's URL structure should be as simple as possible. Consider organizing your content so that URLs are constructed logically and in a manner that is most intelligible to humans (when possible, readable words rather than long ID numbers). For example, if you're searching for information about aviation, a URL like [en.wikipedia.org...] will help you decide whether to click that link. A URL like http://www.example.com/index.php?id_sezione=360&sid=3a5ebc944f41daa6f849f730f1, is much less appealing to users.
While humans may be able to decode odd URL parameters, such as “,,”, crawlers have difficulty interpreting URL parameters when they’re implemented in a non-standard fashion. Software engineer on Google’s Crawling Team, Mehmet Aktuna, says “Using non-standard encoding is just asking for trouble.” Instead, connect key=value pairs with an equal sign (=) and append multiple parameters with an ampersand (&).
It’s difficult for automated programs, like search engine crawlers, to differentiate useful values (e.g., “gummy-candy”) from the useless ones (e.g., “sessionID”) when values are placed directly in the path. On the other hand, URL parameters provide flexibility for search engines to quickly test and determine when a given value doesn’t require the crawler access all variations.
The second is about faceted navigation specifically, but gives some good best/worst practice advice.
To determine the best overall since the advice is a bit different between the two, I think "friendly" with anything unnecessary in a query_string is a good compromise between SERP clicks and bot-understandability [AKA accurate interpretation of parameters].