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The Default category URL shows the last category (before products) and any others preceding that one.
For our example, the rule would translate to 'writing/ballpoint-pens'.
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A typical product URL is usually quite long, and includes all category levels. This is not ideal as an SEO-friendly URL as it is too long and contains details that are not directly relevant to the product and cannot be processed quickly by the user.
You may want to shorten it to contain only the last category, product description and product code, for instance.
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