I hope when you said "compress table", you meant the table with its column values compressed as there is nothing like compress table in teradata (as per my knowledge). And you can always check if the columns of any table are compressed or not by doing SHOW TABLE and looking at its definition.
I agree with KS....show table <table-name> would tell you which columns are compressed...otherwise there is nothing as such compressed table in TD...although we have compressed join index available...hope you are not talking about compressed join index?
This is current as of 13.10, I'm not sure whats available in 14.0.
It depends which type of compression you're talking about. There are 3 main types of compression Multi-Value Compression(MVC), ALC(Algorithmic Compression) AND BLC(Block-Level Compression).
For MVC, you can query the DBC.Columns view, which has a column called CompressValueList, you can get the tables by doing: