Joining Different GNDs

There are times when you need to short or join different nets together at a designated common point in a design such as AGND and DGND. 

In Altium this can be accomplished using NetTies if you have control of the schematic.

If you don't have control of the schematic you will not be able to include a NetTie symbol and NetTie footprint in the design.

One option is to create a short circuit in the design and waive the DRC violation.

For example you could join two different nets using overlapping fills or solid regions.

Another option if you don't want to waive DRCs is to create a rule that allows for the shorted nets.  

To prevent holds and technical queries from your PCB fabricator include notes in the fabrication package that include shorted nets.

That's it !