Transfer data from SQL Server table using query to Excel and vice-versa

Question

I want to transfer data from SQL Server table to Excel sheet using 3 tier architecture in asp.net 3.5. After user has made required changes in the Excel sheet I want Excel sheet to get uploaded and update data in the table with validation for proper data.

Answer 1

您可以设置一个SSIS包以从Excel导入数据

Answer 2

You could either look at libraries (tons of them out there) to programmatically read and write Excel sheets, and handle it all manually.

OR: check out the SQL Server Integration Services (SSIS) - they offer neat ways to export SQL Server data into a multitude of formats (including Excel), and they also offer the route back. You can easily control and execute SSIS packages from a .NET application, too.

Answer 3

I can think of two methods. The first is to make an ADO connection to your SQL/Server from Excel VBA (which can be password protected). When you press a button in Excel, it either reads your spreadsheet data one record at a time and has the validation logic OR it simply uploads it with insert query to a temporary table and then you have a trigger that sees the data and processes it. That way you don't have to upload any files.

I have used ADO commands in VBA to SQL/Server and they are amazingly easy, reliable and exceptionally fast. Plenty of examples out there through Google search to find examples. It's great because you can use all kinds of Excel-specific VBA commands to build a record then update or insert it or whatever you need to do.

For security, you can limit the user (connection string and password hidden in the VBA) -- to just inserting data in a certain database so even if the password is somehow hacked from the VBA it won't do anyone any good as they can only insert.

The second method is to create an ordinary ASP upload control that accepts your Excel file when it is done. There is an event in ASP where you can run ASP.Net code when the file upload is complete. That would see the uploaded Excel file, read it through ordinary .net commands for reading Excel files (Excel automation), process it then I guess either refresh it or discard it. I do not know if there are complications running Excel automation on a server -- probably, because in essence it is running a verison of Excel.Exe on your web server (not really a good idea).

I believe you can make an ADO connection from ASP to an Excel file and do SQL queries on it. I have done that successfully but unfortunately it decides the type of the field based on the first few records and this can sometimes cause a lot of problems when reading an Excel file as a database. I suppose you could write some quick VBA to output the Excel data to CSV and upload that CSV file instead, so that nothing on the web server has to try to read an Excel file. In VBA, you can even automate the upload through SendKeys and InternetExplorer automation. I've done that and it works amazingly well. Sendkeys is the only way to populate the file upload text box for security reasons.

As you can see the first answer is the better one. That is how I would do it because that way you can also refresh your spreadsheet with new data.

I actually think you posted a very interesting question here. It's a lot easier to edit data in an Excel spreadsheet and send it back up. I have replicated a lot of that functionality using the Excel-style grid control from essentialobjects -- great software, but to emulate a spreadsheet takes a lot of coding and still it's just a Excel-like form, not a full spreadsheet.

If you are willing to put MS-Access in the middle, that can get you around a lot of these complications, but is itself an extra layer.