Google will allow you to directly edit a spreadsheet in an iframe. I've got this on some of my sites.
In my case, the sharing in the spreadsheet is set to "Anyone with the link" "Can edit". Not sure how it would work if you require authentication.
Is this possible?
Nope. The Excel Online App currently does not support importing/opening CSV files.
You'll have to convert it to XLSX first, which you could do using Libre/OpenOffice, or one of many online file converter services.
I figured it out, almost by accident. You see how in the original screenshot, the row colors alternate but then stop at row 23. That's because the "table" part of the worksheet only included the top rows, and the filtering only works on those rows. I had to reformat ALL of my data as a table, and now it works. This is really non-obvious.
I'm late in the party but not empty handed.
Yes, Excel online does support filtering.
Just format your column as table and then select the kind of filter you want to apply.
Refer to this technet for complete feature list.
You should create an Excel survey so that nobody knows who else is filling out the form and they can't edit anyone else's responses.
Go to OneDrive
Select New > Excel survey
You will then go through a wizard asking you to create questions.
If you want to make people answer all of them then mark each question as Required.
Add as many questions necessary
The regional settings for Excel online will be determined by the online host, i.e. OneDrive for Business or SharePoint, not by Excel.
In OneDrive for Business, click the cog wheel at the top right, then Site Settings > Regional settings.
Confirm that both the Time Zone AND the Region Locale are set to US time zone and English (United States) respectively....
You need to use TEXT, instead of TO_TEXT:
As long as underlying date number is correct, This will work.
Set formatting in '90diaspessoas'!A16 correctly to DD-MM-YYYY. Then, TO_TEXT will work.
FINAL CONCATENATED FORMULA:
We had the same concern. So we created a new site collection specifically for surveys. Then we turned on the setting "Allow both external users who accept sharing invitations and anonymous guest links: in our Tenant, and turned it off for all site collections except the one we will use only for Excel Surveys.