Every database is different. The complete list of available fields for each database is clearly listed on every product page, including field statistics. This should give you a clear idea as to all of the different items or data that is available for each record, or item in the dataset that is being sold. Reviewing the sample data for each database will also give a clear indication on what to expect.
The Table Schema Database Field Statistics section is in the middle of each product detail page. If you are having issues locating it, just click on FIELD STATISTICS in the Database Help menu on the top right:
Note that the fields listed for databases are the fields available for each recordset. This does not mean that there is actual data in that field for all, or even a majority of the records. If you need statistics on certain field(s) for this database that are complete/filled in please inquire before purchasing. For many of our data collections full field statistics are published on the product page already.