Might be St. Patrick's Ringsend - if the parish priest on the cert is a Rev. Joseph G. Mooney, then the marriage took place here..
The other possibility is St. Mary's Star of the Sea.. technically in Irishtown, but covered Ringsend and Sandymount also. The P.P.s during the early 1900s were a Thomas McGrath and later a Charles Ridgeway.
Just to confirm we are talking about the correct church... what 's the name of the priest on the marriage cert ?
Neither of these parishes have their historic records on IrishGenealogy. I've heard of some people that arranged visits to the Star of the Sea church by appointment to view specific records. It might be worth trying to make contact with the parishes to check. It's usually better to make contact by phone or in writing.
Contact details for Dublin churches are on :
http://www.dublinchurches.com/churches/start.htm(St. Patricks is listed under Ringsend, Star of the Sea under Sandymount)
Shane