code: public TableResult listTableDataSchema(
        String datasetName, String tableName, Schema schema, String field) {
      // [START ]
      TableResult tableData = bigquery.listTableData(datasetName, tableName, schema);
      for (FieldValueList row : tableData.iterateAll()) {
        row.get(field);
      }
      // [END ]
      return tableData;
    }
docs: [VARIABLE "field"]