How to delete all empty rows at once?

@User5510 Select the first record you want to delete then press SHIFT and select down to the last record you want to delete. Right click and click delete records. 

Here's a quick Loom Vid to demo

Arthur's method works if there aren't too many records and if they are all next to each other.

If you have a lot of records, and records with data are intermixed with records without data, you may want to first filter the view to show only records without data. (Use the "is blank" option for all the fields that might have data. If there are a bunch of fields, you can also add a formula field that concatenates the data of all the fields together and then filter on only that formula field.)

Then you can use the select box in the top left corner to select all records in the view. Then right-click and delete.

I've also written a script that will delete empty records, but it isn't in a format for me to publish yet. Sigh. too much to do, not enough time.