Amazon has been providing a lot more data for keywords. Although they're getting better at providing documentation there is still a lot of confusion.
Before I compare the data from SQP to the data in Datarova I'll explain what each of the datasets is showing.
I recommend that any seller that is using SQP data downloads the report for a week and compares the total clicks and sales against their actual clicks and sales for the same week.
Also, compare the conversion rate SQP gives to your conversion rate shown in Business Reports or your PPC reports.
Even when the brand isn't running any advertising or sending any external traffic to Amazon you'll see that the values are different.
Search Query Performance
I'll focus on the Clicks and Purchases counts in SQP as this is the most useful data.
The documentation on Clicks doesn't give much information.
It states that the 'Total Count' for clicks is "The number of ASINs clicked for the query originated from the search result."
They also say that 'ASIN Count' is "The total number of ASIN clicks for this query."
This doesn't tell us much (and it seems like they got the descriptions the wrong way around for the columns!) but the documentation on how total impressions are counted gives more information.
Assuming the ASINs excluded from the impression counts are also excluded from the clicks count then it seems that SQP will include all clicks on an ASIN in the search results except ASINs displayed in widgets.
For Purchases the documentation is quite detailed.
It tells us that SQP calculates purchases as orders placed, not units sold.
It only includes sales that happen within 24 hours of the customer searching for a keyword and clicking on an ASIN.
It means the Purchase won't get counted if a customer searches for the keyword, clicks on an ASIN, adds to cart, and the next day comes back and completes the purchase.
It also won't count Purchases if a customer searches for a keyword, clicks on an ASIN, then clicks on a different ASIN shown on that listing page and buys that.
Datarova Keyword Data
There is an article describing the keyword data shown in Datarova here.
Basically, the Datarova data only counts clicks made after a customer searches for a keyword and then clicks on an organic result in the search results.
Sales are counted as the total units sold and not the number of orders placed in a 24-hour period.
Conclusion
When comparing SQP data to the data in Datarova you'll often find that the clicks in SQP are larger. This is because it counts clicks on sponsored ads and not just organic results.
It's common for the sales in SQP to be lower than Datarova. Some of the reasons for this are because SQP counts orders and not units. If a customer buys 5 units then SQP will show that as 1 sale, and Datarova will show it as 5.
SQP also limits the purchases to ones made within 24 hours of the click and only on the ASIN that was clicked on from the search results.
Both datasets are neither 'right' nor 'wrong'; they show different aspects.
Analyze both sets of data against your brand's data and determine which is more accurate for you.