Opposite of "Dry Run"?

It depends on what you mean by an opposite. Nouns and noun phrases don't always have opposites - e.g. what is the opposite word for hospital, car, etc? It strays into philosophy, but we can consider functional opposites, that is, opposites in the sense of their effect or position, etc.

Since a dry run is a practice event, the candidates that come to mind for an 'opposite' meaning are:

• not practice, i.e. the event itself - event or run (akin to linked definition 5) or execute (linked definition 2); or
• opposite time relative to the event - clean up or tear down.

Update @Michael's comment to the question includes the excellent 'not practice' opposite live run.

The term wet run appears to have at least some usage:

At Brooks International, we use the terms “dry run” and “wet run” to describe activity leading to the “I Date,” where the client’s strategic imperative is fully implemented and beginning to return benefits at the rate required in the initial agreement (cash flow).

A Salem Daily News article from July 6, 1896, describes a contest between fire companies as dry runs (this is the first known usage of the term). The contests did not use water. Fire company drills with water were and may still be known as wet runs.

However, having just run into the same wording problem, I decided to go for non-dry run, for the following reasons:

• in my case (and possibly in yours too), both expressions (dry and non-dry) would appear near each other, making the connection clear.
• non-dry run is understandable on its own and can be easily associated with dry run (personal opinion).
• wet run is practically not used despite my above example (most of the few cases found by Google are from different contexts anyway), and would thus likely be perceived as odd and possibly not understood at all.

You're right – this depends a lot on context. For example, I'm not sure if theater companies would use the same terminology as software companies. (And that makes me wonder: would dress rehearsal be considered a synonym or an antonym for dry run? It seems like it could be used either way – maybe more of an antonym if we used full dress rehearsal.)

Another option that came into my mind was D-Day. In addition to its historical meaning, NOAD provides this definition:

D-Day (noun) the day on which an important operation is to begin or a change to take effect

It wouldn't be a universally-applicable "antonym" for dry run, but I've heard it used every now and then to refer to a momentous date requiring a lot of coordination (say, a wedding day). I found one message board where a contributer used D-Day to refer to the day she'd quit smoking¹. The Independent used the term in a business context²:

Argos is gearing up to be able to stand on its own two feet after being demerged from its parent company, GUS. D-day is on Wednesday, when shares in ARG ... will trade as a separate company.

So, it doesn't seem like too much of a stretch say something like:

We'll have a dry run on the 23rd; D-Day is on the 25th.

I'm late to the party, but in my case the dry run is only a partial portion of my code - it stops short of doing dangerous things. So I'm using complete as the opposite of dry run. I suppose whole, entire, or full would do.