A tabulation groups rows of data together based on the values in one or more columns and performs calculations on data in each of those groups. The summarization results are provided in a small, easy-to-read table.

A tabulation is a great place to start when you want to get a feel for what all those rows of data in your table really mean. Tabulations allow you to calculate various metrics, such as the sum, average, or highest value of a particular column, grouping those calculations based on common values in one or more other columns. For instance, in a table containing weather data, you could calculate the highest temperature during the year for every unique combination of ZIP Code and month in the table.

In this tutorial, you will perform a tabulation on the Sales Item Detail table in the Trillion-Row Spreadsheet (TRS) to find the total amount of sales for each of three stores in a chain. You will then perform a separate tabulation to calculate the total sales amount and number of items sold in each transaction. Finally, you will export the tabulation to a Microsoft Excel workbook file.

To perform a tabulation:

Next, choose the column by which you want to group the information. In other words, specify how you want to subtotal the data. When performing a tabulation, a helpful question to ask yourself is "What values do I want to use to group the records?" Since you want to find the total amount of sales for each store, you should group the information by the Store column. Grouping is a way of pooling all the records for a single entity or value (in this case, a store) into a single entry in the table.

Now that the data grouping is set, choose the data you want to summarize. Since you want to find the total amount of sales, you should summarize the Sales column.

The summarization is a combination of the selected column and the default tabulation function for that column's data type. In this case, sum is the default tabulation function for Sales. This means the sum of Sales summarization will calculate the total amount in the Sales column.

The next step of a tabulation is to select the tabulation function you want to perform on the column. This is done by clicking the summarization (in this case, sum of Sales) and choosing a tabulation function from the menu.

However, since the default tabulation function happens to be exactly what you are looking for, you do not need to make this selection.

At this point, your tabulation should look like the following image.

Starting from the right and working left, the tabulation panel indicates that the resultant worksheet will contain a single column (Sales) and each row in that column will list the total sales amount (sum of Sales) grouped by Store.

By default, columns in the resultant
worksheet are named `t0`, `t1`,
`t2`, and so on. You can give the tabulated columns more
meaningful names within the More Options view of the
Tabulation panel. In addition, you can define the
format of the tabulation.

Now that you have selected the data you want to group by, the data you want to summarize, and the formatting options, generate the tabulation.

Now, you will take a look at a slightly more complex example of a tabulation.

Instead of looking at the total sales per store, you will determine the sales totals for each transaction in the Sales Item Detail table. However, you also want to know at which store any given transaction took place, and also the total number of items in each transaction. The objective is to have a summary table that shows you the transaction ID, store, sum of sales, and total units for each transaction. To accomplish this, you will edit the existing tabulation operation in the timeline.

Just as before, start by selecting a column to group your data. In this case, you want to see the total sales figures for each transaction. You also want to know which store recorded each of the transactions in the table, so you should also group by store.

Now that you have grouped your data, first by transaction, then by store, you can choose the data you want to summarize. In this example, you are still summarizing sales, so you can leave the sum of Sales summarization and simply add the summarization of units.

Since the default tabulation function (sum) is what you want, once again you do not need to select a tabulation function from the menu.

The tabulation panel indicates that the resultant worksheet will contain two columns, Sales and Units. The rows in each column will list the total sales amount (sum of Sales) and total number of items sold (sum of Units) grouped first by Transaction and then subgrouped by Store.

Next, as before, give the new tabulated column a more meaningful name and define the formatting.

Now that you have selected the data you want to group by and the data you want to summarize, generate the tabulation.

The final step in this tutorial is to download your results in a Microsoft Excel workbook file.

After you are comfortable with them, tabulations are a very fast and powerful way to
get a sense of what information your data contains and how it can be leveraged to make
decisions. So with that in mind, good luck and keep
practicing.