It depends on what you mean by "oceanic transgression." I only minored in geology, so I'm not as versed in many of the detailed and technical terminology of specific disciplines
within geology, but I don't recall that term being used. So if I look at it as one of your usual made up, bullshit terms, then, on the face of it, you mean how many times has the ocean covered the continents.
This, my good man, will depend upon which continent and when, since the continents are each on their own tectonic plates which have changed position, size, density and constitution with time. Therefore, the answer to your question could be millions of times, thousands of times, or hundreds of times -perhaps even a handful of times to never -depending on when/where you are.
In other words, this is a non-question -a nonsense, creationist bullshit question that has no scientific basis beyond your imagination. If I'm wrong, please cite the scientific literature that discusses the topic an allow me to revise my position, which I will do cheerfully with the right data.
Also, either participate in discussion or not. If you choose "not," keep creating posts that are spam, meaningless, or trolling in nature and we'll all get to see you again in three days.
and what is your evidence for that number?
Again, it depends upon
where, but in general the evidence is the sedimentary deposition in the locality itself. I regularly visit several "beaches" of 65-125 million years ago and collect Inoceramus, Texigryphaea , amnonites, etc. They all have different chronometric periods to which they date that range as above and are found in members that under/over-lay each other. In one locality I can visit the Austin Chalk and the Eagleford Shale in a single place due to recent construction and I can follow these members west and see where each overlaps the next for millions of years. Sometimes beach, sometimes dryland.