private Set<String> getTableNames(String arguments) {
    Set<String> ret = new HashSet<String>();
    String[] tables = arguments.split(",");
    for (String string : tables) {
      string = string.trim();
      if (string.length() == 0) {
        continue;
      }
      ret.add(string);
    }
    return ret;
  }
Datasets are provided by this handler.

An invocation of:

<pre>
--! qt:dataset:sample
--! qt:dataset:sample:ONLY
</pre>

will make sure that the dataset named sample is loaded prior to executing the test.
itests/util/src/main/java/org/apache/hadoop/hive/ql/dataset/QTestDatasetHandler.java