What is Tableau Index Function?
Sometimes, you need a numbering system to number the rows in your table. It works when you need to call certain elements by their index number in a small table or find the feature specifics of a certain index element by querying it. Fortunately, Tableau has a default function called Index, which is a default table calculation that is available in Tableau. The INDEX function in Tableau can not only be used for the main calculation, as shown in the example below, but tableau Index by dimension is also possible.
Here, a calculated field called “INDEX” was created and declared for the feature “Ship Mode.” If you observe, a new index element was created for every different element in the Ship Mode.
Table of contents
Key Takeaways
- The INDEX() function in Tableau assigns sequential indexes to rows within a dataset, providing a unique identifier for each row.
- It is commonly used for tasks such as creating unique identifiers, ranking data, or establishing row order.
- INDEX() can be customized with partitioning and ordering options, allowing users to define how indexes are calculated within specific groups or categories in the data.
- One key advantage of INDEX() is its dynamic nature, as it automatically adjusts indexes when the underlying data changes, ensuring consistency and accuracy.
- However, it has limitations in handling tied values and may require careful consideration for performance with large datasets.
Syntax
The syntax to use the Tableau Index Calculation is as shown:
INDEX()
This default table calculation can also be used to define the dimensions of various features in a table.
How to use the Index Function in Tableau?
Follow the simple steps below to learn how to use the Tableau Index Calculation appropriately.
Step 1: Once you open the Tableau application, create a new workbook to start working on your dataset.
Step 2: Drag and drop or select the file you want to import and analyze in Tableau.
Download and use the Sample-Superstore dataset for your purposes. The first sheet will be created by default in every new workbook.
Step 3: Go to the worksheet after importing the data in the workbook.
Step 4: To use the Tableau Index calculation, you need to define it in a new calculated field. To do so, create a new calculated field.
Step 5: Name the calculated field and then call the INDEX function in Tableau. Then, apply the changes.
Step 6: From the features, select “Category” and “Sub-Category” and place them in the “Rows” component.
Step 7: Drag and drop the INDEX field that you have created earlier. Since the result is numerical, it will be stored as a Measure. To get the accurate values, right-click on the calculated field and select “Discrete.”
Step 8: Rearrange the Tableau Index Column to make the table more coherent.
The resulting table was created using the Tableau INDEX function.
How do you create an index in Tableau?
To create an Index in Tableau, you need to follow a few steps since it is a Table calculation.
Step 1: Create a new calculated field.
Step 2: Name the field and call the INDEX function.
Step 3: Close the calculated field and use it for your needs. You can perform a variety of tasks which are very helpful for categorization and so on.
Examples
You can go through the different ways in which the Tableau Index function can be used. The Index function in Tableau is extensively used, as seen from these examples.
Example #1 – Find the position of rows using the Tableau INDEX function
When you have a table built in Tableau with the columns you need, you want to add an index that numbers all the rows depending on the fields and the dimensions that you’ve selected. Follow these steps to accurately define the position of the rows using the Tableau INDEX function.
Step 1: Connect your desired dataset to a new workbook. Here, the Sample-Superstore dataset is used.
Step 2: In the worksheet, start by creating a calculated field to define the INDEX function.
Continue further once these steps are defined.
Step 3: Select “Ship Mode” and “Segment” from the Dimensions and place them in the “Rows” component.
Step 4: Drag and drop the INDEX field that you’ve created. Right-click on it and select “Discrete.”
Create another copy of the INDEX field by pressing the “Ctrl” and the left-click button to create 2 INDEX fields. The “Rows” component now looks like this.
Step 5: Right-click on the INDEX field before the segment and select “Edit Table Calculation.”
Step 6: In the Table Calculation popup, select “Specific Dimensions” and select “Segment.”
Step 7: Similarly, right-click on the other INDEX field and edit its table calculations.
Step 8: In the Table Calculation popup, select “Ship Mode” under “Specific Dimensions”.
It is the final table.
With this, the position of rows could be defined and found.
Example #2 – Find the position of rows start with specific field
In this example, you can learn how to start with a specific index field. It can be done by starting with a different number, say 0, which you can define using the Tableau Index Calculation field. Follow these steps side-by-side to learn more.
Step 1: In a new workbook, import the Sample-Superstore dataset and go to the first worksheet.
Step 2: Create a calculated field to start the index with a specific field.
Step 3: Name the field and define the Index. Here, since you want to start the index from 0, you need to subtract 1 from the Tableau INDEX value. This is used to divide the values of the feature “Segment” in the dataset.
Step 4: Place the features “Region” and “Segment” in the “Rows” component.
Step 5: Drag and drop “Sales” in the empty column.
Step 6: Right-click on the SegIndex field and select “Edit Table Calculation”.
Step 7: In the Table Calculation, select “Specific Dimensions”. Under that, select “Segment”.
This is the final table.
Example #3: Show the top N numbers of rows only
Sometimes, you have to parse through datasets that have many data points. In such cases, it is prudent to categorize them using the INDEX function. By using the filtering option in Tableau, you can view a certain index range. To learn how to do this, follow the steps below.
Step 1: Import the database into a new workbook. Here, the Sample-Superstore dataset is used.
Step 2: Create a calculated field to call the INDEX function.
Name the field and use the INDEX function.
Step 3: Place “INDEX” on the “Marks” tab. Right-click on the “INDEX” and click on “Discrete”.
Step 4: Place “Sales” in the “Columns” and the INDEX field and the State in the “Rows”.
Step 5: On top of the graph, click on the “sort” icon. The graph will be ordered in descending order.
Step 6: Create a new calculated field to filter the top N indices.
Step 7: In the calculation field, name the field and select the INDEX field that you have declared, not the default table function.
Then, categorize the index based on groups of 10.
Step 8: Drag and drop the Index Filter calculated field to the “Filters” tab.
Step 9: In the “Filter” tab, click on “All” to include the ranges defined.
Step 10: Right-click on the Calculated field in the filter and select “Show Filter”.
This creates a tick-box with the ranges you can check and uncheck to see the sales data even better.
This is the graph created.
You can filter the rows that you can see with Tableau.
Important Things To Note
- Clearly understand why you’re using the INDEX() function. It’s often used for creating sequential indexes for ranking, sorting, or identifying specific rows in your data.
- Utilize the INDEX() function within calculated fields to create new fields with sequential indexes. This allows for flexibility in analysis and visualization.
- Use the INDEX() function with the appropriate partitioning to calculate indexes within specific groups or categories in your data.
- Avoid mixing aggregated and non-aggregated expressions within the same calculated field when using INDEX().
- Don’t neglect performance optimization. If your workbook is running slowly, revisit your calculations involving INDEX() and consider alternative approaches to achieve the same results more efficiently.
Frequently Asked Questions (FAQs)
In some cases, the Tableau index not working problem would lead to disastrous consequences. Here are some of the limitations of using the INDEX function.
• Limited flexibility in handling tied values.
• Index values are solely based on row position, not on specific data attributes.
• Does not provide dense ranking or competition ranking options.
• It may lead to confusion if used improperly due to its strict sequential nature.
• Index values can be affected by data partitioning and sorting, requiring careful consideration.
Yes, you can combine INDEX() with other functions.
• It can be used with WINDOW_SUM(), WINDOW_AVG(), etc.
Yes, the INDEX() function dynamically adjusts its values as data updates within Tableau. Whenever there are modifications or additions to the dataset, the INDEX() function recalculates indexes accordingly, ensuring that the sequential numbering remains consistent and reflects the current state of the data. This dynamic behavior enables users to rely on INDEX() in Tableau a great analysis, as it adapts to changes in the underlying dataset, maintaining accuracy and relevance over time.
Download Template
This article must help understand the Tableau INDEX formula and examples. You can download the template here to use it instantly.
Recommended Articles
This has been a guide to Tableau Index. Here we learn how to Create and use index function in Tableau with syntax, examples, points to remember & template. You can learn more from the following articles –
Leave a Reply