If possible, it is best to use a Sailthru Content Feed as your email's data feed because they by default provide the following:
- Other standardized Sailthru metadata to utilize with the personalize() function and some other functions (ex. standardized date for using with the sort() function)
These are, however, some instances where a single feed (custom feed) may be a better option for your implementation. A few of these are:
- Tagging on individual content page is not adequate
- You utilize custom data cannot be added to the Sailthru Content library (either because you are unable to utilize the Content API or are unable to add via custom meta tags)
- You cannot limit yourself to Sailthru's limit of 3000 items in one feed
These single (custom) feeds must meet the following criteria:
- Be formatted as either RSS/XML or JSON
- Be under 10mb (though smaller sizes are best if possible and will help things load more quickly)
- Contain a field named 'url'
An example where a single feed might be a better option (than a Sailthru Content Feed) is something called a Reorder Email Series:
In this example, a client wants to send an email to their users to remind them to reorder an item they have likely run out of (for example, if they ordered vitamins 3 months ago, an email to remind them to buy more vitamins).
There may be a situation where those vitamins are not in stock, and the client does not in this case want to include them in the email. To do this, you could build a feed that has only the SKU codes of your valid in stock products
At that point, you would be able to match to see if the sku on the item var matches a sku in the feed. If it does, it can be pushed into the template reminding the user to reorder. If it is not there, it would not be added to the template.