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Click_id will be detected by a cookie.
What type should be used:
POSTBACK - if advertiser has the ability to send requests to our system from his back-end. Advertiser should store on his side click ID which he will send in postback request.
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To prevent occurrence of conversion duplicates in both you should add into it TXN ID with unique identifier of for example saleID (order ID on the advertiser side)
Rate and Sale amount parameters:
sale_amount - if we can't get exact payout from an advertiser.
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