I'm looking for tools that connect Quickbooks desktop to SQL server. I'd love to have a function on a schedule to download fresh data from QB into SQL server, and then also upload data from SQL into QB.
Anyone have any recommendations?
That part seems improbable (but I know next to nothing about QuickBooks). For anything that actually twiddles with the data I would expect to have to use an API into QuickBooks and "import" Invoices / Journals / New/Changed name records, etc.
Getting the data out, so that you have some sort of Read Only copy, in SQL (e.g. to then "combine" with other SQL data for Management Reports or somesuch) should be straightforward - even if all you can get out of QuickBooks is some sort of CSV file ... hopefully it will export something more easily imported into SQL "UNambiguously", which CSV very rarely is, IME.
It is Not Easy I suggest you to hire professional for sync quickbooks to sql server.