right. robots.txt will keep the honest bots out of store directories. however, that is not an issue unless you have links to files and or folders in the store which you don't or shouldn't. so you're back to square one because all links contain cart_ids from the second store page visited onwards. with the exception of returning from the viewcart page and some other functions.
there are several ways to prvent the cart_id from displaying in a link or address...
you can strip the cart_id=(%%cart_id%%) from all scripts and links. this will prevent the cart id from displaying in the query string. this is not recommended. however, i know ppl who claim this has never presented a problem for any of their customers.
you can do a product link list out side of the store linking to each product with p_id and not product. in the store headers put the meta tag no-follow. this will have some limited success.
you can do a complete online catalog outside for the store linking to the product, the product category and other destinations of your site. included in the product catalog would be the product description, price is not necessary. then do a robots text telling all bots to stay out of your store directory...
http://www.hgltd1.com/
the store is in the hgltd1 sub directory, for example
http://www.hgltd1.com/hgltd1/category-Bracelets.htm
the online catalog (my static page generator) is in the Catalog subdirectory
http://www.hgltd1.com/Catalog/index.html
i choose to keep bots out of several directories including the store. since all information relative to search engines can be found in the catalog there is absolutely no reason to allow bots to index the store's dB. so, i created this robots.txt to keep them out...
http://www.hgltd1.com/robots.txt
awhile back i updated the robots.txt and omitted the hgltd1 subdirectory for experimental reasons so if you have the google tool bar you will see a pr where there shouldn't be.
one more way to prvent the cart_id from being included in the urls/links is to do a mod rewrite. this is not a cure all unless the store is massively hacked to allow for rewrite throughout. at hgltd1.com you will see the store with mod rewrite in the hgltd1 subdirectory.
my personal opinion? the online catalog is the best way while keeping bots out of the store. it's a lot of work to do by hand but worth it. it's also tons easier to use the online catalog generator.
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