Shower drain: How best to connect PVC to ABS?

I am putting in a shower on a slab floor and I have jackhammered a hole in the slab to get to some previously-installed, roughed-in drain piping. (There is also a separate vent pipe already installed for the shower.) The existing drain piping is ABS and the specialty base that came with my linear drain is PVC. I'll be cementing an ABS P-trap to the ABS piping, but then I need to transition from the P-trap to the outlet from the PVC drain. Once I'm done with the work, I'll be dumping a bag of sand over the P-trap assembly, and refilling the hole in the slab with 4"-5" of concrete. Since this drain won't be accessible in the future, what is the most secure way to do the ABS-PVC connection? The two approaches I am considering are:
1. Use Oatey ABS-PVC transition cement to connect the two pipes with a 2" coupling.
2. Use PVC cement to attach a 2" PVC female-threaded fitting to the PVC drain base; use ABS cement to attach a 2" ABS male threaded fitting to the existing ABS piping; wrap the threads with teflon tape, and screw the two fittings together.

Please comment on either of these two approaches...or anything better you can suggest. Thanks.

A buried connection can use a Fernco flex coupling.

jadnashua said:

A buried connection can use a Fernco flex coupling.

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Fernco coupling: absolutely the best way to go. What I would do different in your installation is do not use any new ABS, use PVC for the P-trap etc. and use the Fernco coupling where you connect the new PVC to the existing ABS after the trap. I make a lot of money replacing cracked ABS traps and would like to save you future aggravation.