TDA-C01 Tableau Certified Data Analyst Exam Questions and Answers

Replace Data Source

Replace Data Source is a feature that allows you to replace one data source with another one that has the same or similar fields and structure. It updates all the worksheets that use the original data source with the new one, without reloading the data. In this case, you want to replace the data source that contains order data from 2019 with the one that contains order data from 2020.

To replace the data source, you need to do the following steps:

• Go to the Data Source tab at the bottom of the workbook to see the data source page. You will see a table that shows the fields and values from the original data source.
• Click on the drop-down arrow next to the data source name at the top of the page and select Replace Data Source from the menu. This will open a dialog box that allows you to replace your data source with another one.
• Select the data source that contains order data from 2020 from the list of available data sources and click OK. This will replace your original data source with the new one and update your worksheet accordingly. You may need to fix any broken fields or calculations that result from the replacement.

References: https://help.tableau.com/current/pro/desktop/en-us/datasource_replace.htm https://help.tableau.com/current/pro/desktop/en-us/datasource_replace_workbook.htm

A data source filter is a filter that applies to all the worksheets that use the same data source. It filters the data before any other filters or calculations are applied. You can add a data source filter from the Data Source page by clicking on the Add button next to Filters.

The type of filter that will appear in the Edit Data Source Filters dialog box is a dimension filter on all the sheets. This means that you can choose a dimension from your data source and filter it by values, range, condition, or top/bottom. The filter will affect all the worksheets that use that dimension.

The other types of filters are not data source filters and will not appear in the Edit Data Source Filters dialog box. A table calculation filter is a filter that applies to a table calculation, such as percent of total or running total. A top N condition filter is a filter that shows only the top or bottom N values of a measure or dimension based on a condition. A context filter is a filter that creates a subset of data that other filters can use.

References: https://help.tableau.com/current/pro/desktop/en-us/filtering_datasource.htm https://help.tableau.com/current/pro/desktop/en-us/filtering.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_tablecalculations.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_topn.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_context.htm

Data source filters in Tableau apply to the entire data source, affecting all sheets that use that data source. The Edit Data Source Filters dialog box allows you to add filters that operate at the data source level, which is different from context filters, top N filters, or table calculation filters that are applied at the worksheet level.

The correct order of the three actions is:

• From the connections pane, connect to both data sources
• Join both datasets and select the join type
• Specify Employee Name as the join key

The first action is to connect to both data sources from the connections pane in Tableau Prep. The connections pane is where you can access and add data sources to your flow. You can connect to various types of data sources, such as Excel, SQL Server, or Tableau Server. In this case, you want to connect to an Excel worksheet and a SQL Server table.

The second action is to join both datasets and select the join type. A join is a way of combining data from two or more tables based on a common field. You can join datasets by dragging one table to the canvas and dropping it on top of another table. This will create a join step in your flow. You can select the join type from the drop-down list on the join step. The join type determines which rows are returned from the tables.

The third action is to specify Employee Name as the join key. A join key is a field that is used to match rows from different tables. You can specify the join key by clicking on the field name in each table and dragging it to the center of the join step. This will create a join clause that shows the field name and the operator. In this case, you want to use Employee Name as the join key, because it is a common field between the two datasets.

The other options are not relevant for this scenario. Specifying Department and Team Size as a join condition will not work, because they are not common fields between the two datasets. Opening both data sources in Tableau Desktop will not help you join them in Tableau Prep. Adding a step to aggregate the data in the SQL Server table will not affect the join, but it may change the level of detail of your data. References: https://help.tableau.com/current/prep/en-us/prep_connect.htm https://help.tableau.com/current/prep/en-us/prep_join.htm https://help.tableau.com/current/prep/en-us/prep_join_types.htm

The LAST() function in Tableau returns the number of rows from the current row to the last row in the partition. When you compute using 'Order Date', it will change the partitioning of the calculation. If 'Consumer' in '2018' is the last row in its partition when computed by 'Order Date', then LAST() will return 0 for that cell.

The LAST() function in Tableau is a table calculation that returns the number of rows from the current row to the last row in the partition. The value of LAST() is 0 for the last row, increases by 1 for each row above the last row, and can be negative for rows below the current row if there are such rows in the partition.

In the provided visualization, LAST() is set to compute using Table (across). Changing the compute mode to use "Order Date" will adjust the partitioning of the data upon which the LAST() function is calculated. Since "Order Date" is likely to be a unique value per row (assuming each order has a unique date), each row becomes its own partition.

For the Consumer segment of the year 2018, if "Order Date" is unique for each row, then the last row in each partition (in this case, each individual row) will have a LAST() value of 0 because there are no other rows in the partition - it's the last row of its own partition.

Therefore, when you change the compute mode of LAST() to use "Order Date", each cell under the Consumer segment for the year 2018 will have the LAST() value of 0, because each order date creates a partition of one, making every row the last in its partition.

To use the City dimension to create a dynamic filter that shows the cities that have a population greater than one million, you should use a condition filter. A condition filter is a type of filter that shows only the values that meet a specified condition based on a measure or a calculation. You can create a condition filter by dragging a dimension to the Filters shelf and selecting Condition from the dialog box. Then you can enter a formula or choose an option that defines your condition.

In this case, you want to create a condition filter based on Population, which is a measure. You can drag City to the Filters shelf and select Condition from the dialog box. Then you can choose By field from the tab and select Population > Sum > Greater than > 1000000 from the drop-down lists. This will create a condition filter that shows only the cities that have a sum of population greater than one million.

The other options are not correct for this scenario. A general filter is not a specific type of filter, but a term that refers to any type of filter in Tableau. A wildcard filter is a type of filter that shows only the values that match a specified pattern or string, such as “New*” or “*ton”. A top filter is a type of filter that shows only the top or bottom N values of a measure or dimension based on a ranking or an aggregation. References: https://help.tableau.com/current/pro/desktop/en-us/filtering.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_condition.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_wildcard.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_topn.htm

There are different ways to prepare the data in Tableau Prep, but one possible answer is:

Answer area:

• Join the tables.
• Aggregate the data by Sales Team.
• Add the following filter to the Employees table: Sale Team - Team Alpha.

 To analyze sales trends over time for every sales team, you need to combine the data from the Orders and Employees tables. You can do this by joining the tables on the Rep ID column, which is a common identifier for both tables. This will create a single table with all the columns from both tables. Next, you need to aggregate the data by Sales Team, which is the level of analysis you want. You can do this by grouping the data by the Sales Team column and applying an aggregation function (such as sum, average, count, etc.) to the other columns that you want to measure (such as Total Amount, Rep Tenure, etc.). This will create a summary table with one row for each sales team and the aggregated values for the other columns. Finally, you need to filter the data to focus on a specific sales team, such as Team Alpha. You can do this by adding a filter to the Employees table and selecting only the rows where Sales Team equals Team Alpha. This will remove the rows for other sales teams and keep only the data for Team Alpha.

References:

• [Tableau Certified Data Analyst Exam Prep Guide], page 9, section “Preparing Data”
• [Tableau Help: Join Your Data]
• [Tableau Help: Aggregate Your Data]
• [Tableau Help: Filter Your Data]

To modify the chart to show only min and max values of both measures in each region, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the Line worksheet.
• Click on the Line tab at the bottom of the workbook to open the worksheet. You will see a line chart that shows the sales and profit for each month by region.
• Drag Month from the Columns shelf to Filters shelf. This will open a dialog box that allows you to filter by different criteria.
• Select Range of Dates from the dialog box. This will show you options to filter by a range of dates or values.
• Select Minimum and Maximum from the drop-down list next to Month. This will filter by the minimum and maximum values of Month for each region. You can also enter specific values or use the sliders to adjust the range.
• Click OK to apply the filter. You will see that the line chart now shows only min and max values of both measures in each region.

References: https://help.tableau.com/current/pro/desktop/en-us/filtering.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_range.htm

To add a distribution band on Profit to show the standard deviation from -1 to 1, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the SalesVSProfit worksheet.
• Click on the SalesVSProfit tab at the bottom of the workbook to open the worksheet. You will see a scatter plot that shows the relationship between Sales and Profit for each Sub-Category.
• Click on the Analytics tab on the left side of the workbook to open the Analytics pane. You will see a list of analytical objects that you can drag and drop onto your worksheet.
• Drag Distribution Band from the Analytics pane to Profit on the Rows shelf. This will add a distribution band on Profit that shows the average and confidence interval for each Sub-Category.
• Click on the Edit button on the distribution band to open the Edit Distribution Band dialog box. You will see options to customize your distribution band.
• Change the Band From value to -1 and the Band To value to 1. This will change the distribution band to show the standard deviation from -1 to 1, which means one standard deviation below and above the average.
• Click OK to apply the changes. You will see that the distribution band now shows a narrower range of values for Profit.

References: https://help.tableau.com/current/pro/desktop/en-us/analytics.htm https://help.tableau.com/current/pro/desktop/en-us/analytics_distributionband.htm https://help.tableau.com/current/pro/desktop/en-us/analytics_distributionband_edit.htm

To replace the existing data source with the Netflix_2019 data source, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the Movie Durations worksheet.
• Click on the Movie Durations tab at the bottom of the workbook to open the worksheet. You will see a bar chart that shows the number of movies by duration for the existing data source.
• Go to the Data Source tab at the bottom of the workbook to see the data source page. You will see a table that shows the fields and values from the existing data source.
• Click on the drop-down arrow next to the data source name at the top of the page and select Replace Data Source from the menu. This will open a dialog box that allows you to replace your data source with another one.
• Select Netflix_2019 from the list of available data sources and click OK. This will replace your existing data source with the Netflix_2019 data source and update your worksheet accordingly. You may need to fix any broken fields or calculations that result from the replacement.

References: https://help.tableau.com/current/pro/desktop/en-us/datasource_replace.htm https://help.tableau.com/current/pro/desktop/en-us/datasource_replace_workbook.htm

To filter the table to show the Top 10 NOC based on the number of medals won, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the Disciplines worksheet.
• Click on the Disciplines tab at the bottom of the workbook to open the worksheet. You will see a table that shows the NOC, discipline, and medals for each country.
• Drag Medals from the Measures pane to the Filters shelf. This will open a dialog box that allows you to filter by different criteria.
• Select Top from the dialog box. This will show you options to filter by the top or bottom values of a field.
• Enter 10 in the text box next to By field. This will filter by the top 10 values of Medals.
• Select NOC from the drop-down list next to By field. This will filter by the top 10 values of NOC based on Medals.
• Click OK to apply the filter. You will see that the table now shows only 10 rows, one for each NOC with the highest number of medals.

References: https://help.tableau.com/current/pro/desktop/en-us/filtering.htm https://help.tableau.com/current/pro/desktop/en-us/filtering_topn.htm

To add the Sales by State sheet in a Show/Hide button to the right side of the dashboard, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the sales dashboard.
• Click on the sales dashboard tab at the bottom of the workbook to open the dashboard. You will see a dashboard that shows various charts and filters related to sales data.
• Drag Sales by State from the Sheets pane to the right side of the dashboard. This will add the sheet as a floating element on the dashboard. You can resize and position it as you like.
• Right-click on Sales by State and select Add Show/Hide Button from the menu. This will add a button that allows you to show or hide the sheet on the dashboard. You can customize the appearance and behavior of the button by clicking on it and using the options on the Marks card.
• Optionally, you can drag a vertical layout container from the Objects pane to the right side of the dashboard and place Sales by State and its button inside it. This will help you organize your dashboard elements and align them neatly.

References: https://help.tableau.com/current/pro/desktop/en-us/dashboards.htm https://help.tableau.com/current/pro/desktop/en-us/dashboards_showhide.htm https://help.tableau.com/current/pro/desktop/en-us/dashboards_create_layouts.htm

To create a histogram on the Quantity field by using bin size of 3, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that uses the Superstore data source.
• Click on the Histogram tab at the bottom of the workbook to open the Histogram worksheet. You will see a blank worksheet with no marks.
• Right-click on Quantity in the Measures pane and select Create Bins from the menu. This will open a dialog box that allows you to create bins for the Quantity field. Bins are groups of values that are treated as one unit in a histogram.
• Enter 3 in the Size of bins text box. This will set the bin size to 3, which means that each bin will contain values that are 3 units apart. For example, one bin will contain values from 0 to 2, another bin will contain values from 3 to 5, and so on.
• Click OK to create the bins. You will see a new field named Quantity (bin) in the Measures pane with a # sign next to it.
• Drag Quantity (bin) from the Measures pane to Columns on the worksheet. This will create a histogram that shows the distribution of Quantity by bins. You will see bars that represent the frequency or count of values in each bin.
• Optionally, you can adjust the width, color, and labels of the bars by using the options on the Marks card. You can also add filters, tooltips, or annotations to enhance your histogram.

References: https://help.tableau.com/current/pro/desktop/en-us/histograms.htm https://help.tableau.com/current/pro/desktop/en-us/calculations_bins.htm https://help.tableau.com/current/pro/desktop/en-us/buildmanual_histograms.htm

In Tableau dashboards, floating elements are those that can be freely moved over the dashboard canvas without being snapped into the tiled layout. The floating elements are often indicated by their standalone frames and the ability to overlap with other dashboard items. From the provided image, the state filter and the Rate of Obesity chart can be identified as floating if they can be moved independently of the tiled grid layout that constrains other elements.

To refresh an extract on Tableau Server, you need to select the workbook, select Refresh Extracts, and then add a new extract refresh. You can specify the frequency and time of the refresh, as well as any custom options. You can have multiple extract refreshes for the same workbook with different schedules. References: https://help.tableau.com/current/server/en-us/refresh_extracts.htm https://help.tableau.com/current/server/en-us/refresh_extracts_add.htm

On Tableau Server, you can manage the scheduling of extract refreshes by selecting the specific workbook and configuring additional refresh schedules as needed. This allows for multiple refresh triggers, such as the regular Monday at 10:00 AM schedule, as well as an additional trigger for the last day of the month at 18:00.

To split the Customer Name field into two fields named First Name and Last Name, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that uses the Superstore data source.
• Go to the Data Source tab at the bottom of the workbook to see the data source page. You will see a table that shows the fields and values from the Superstore data source.
• Right-click on Customer Name in the table and select Split from the menu. This will split the field into two fields based on a separator, which is a space by default. You will see two new fields named Customer Name - Split 1 and Customer Name - Split 2 in the table.
• Right-click on Customer Name - Split 1 and select Rename from the menu. Type First Name as the new name and press Enter. This will rename the field as First Name.
• Right-click on Customer Name - Split 2 and select Rename from the menu. Type Last Name as the new name and press Enter. This will rename the field as Last Name.

References: https://help.tableau.com/current/pro/desktop/en-us/datasource_prepare.htm https://help.tableau.com/current/pro/desktop/en-us/split.htm https://help.tableau.com/current/pro/desktop/en-us/renamefield.htm

To modify the bar chart to show the percentage of sales for each Subcategory within every Category, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the CategoryPercentage worksheet.
• Click on the CategoryPercentage tab at the bottom of the workbook to open the worksheet. You will see a bar chart that shows the total sales for each Subcategory across all Categories.
• Right-click on Sales on the Columns shelf and select Add Table Calculation from the menu. This will open a dialog box that allows you to apply a calculation to your measure.
• Select Percent of Total from the Calculation Type drop-down list. This will calculate the percentage of sales for each Subcategory out of the total sales for all Subcategories.
• Select Category from the Compute Using drop-down list. This will calculate the percentage of sales for each Subcategory within every Category, instead of across all Categories. The total percentage for every Category will be 100%.
• Click OK to apply the table calculation. You will see that the bar chart now shows the percentage of sales for each Subcategory within every Category.

References: https://help.tableau.com/current/pro/desktop/en-us/calculations_tablecalculations.htm https://help.tableau.com/current/pro/desktop/en-us/calculations_tablecalculations_create.htm https://help.tableau.com/current/pro/desktop/en-us/calculations_tablecalculations_percentoftotal.htm

To filter the table to show the members of the Top10 set and the Bottom10 set, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that contains the Disciplines worksheet.
• Click on the Disciplines tab at the bottom of the workbook to open the worksheet. You will see a table that shows the disciplines, sales, and profit for each salesperson.
• Click on the drop-down arrow next to Salesperson on the Filters shelf. This will open a menu that allows you to filter by different criteria.
• Select Set from the menu. This will show you the sets that are available for the Salesperson field. You will see Top10 and Bottom10 as two sets that have been created based on the sales ranking.
• Check the boxes next to Top10 and Bottom10. This will filter the table to show only the members of these two sets. You can also click on All to deselect all other values.
• Click OK to apply the filter. You will see that the table now shows 20 rows, 10 for each set.

References: https://help.tableau.com/current/pro/desktop/en-us/sets.htm https://help.tableau.com/current/pro/desktop/en-us/filtering.htm

To create a filled map to show the distribution of total Sales by State across the United States, you need to do the following steps:

• Open the link to Book1 found on the desktop. This will open the Tableau workbook that uses the Superstore data source.
• Click on the Map tab at the bottom of the workbook to open the Map worksheet. You will see a blank worksheet with no marks.
• Drag State from the Dimensions pane to Detail on the Marks card. This will create a map that shows each state as a mark. You may need to zoom in or out to see the whole map.
• Drag Sales from the Measures pane to Color on the Marks card. This will create a filled map that shows the distribution of total Sales by State across the United States. The color legend will show you the range of values and colors for Sales.
• Optionally, you can adjust the color scheme, transparency, size, and borders of the marks by clicking on the Color menu on the Marks card. You can also add labels, tooltips, or filters to enhance your map.

References: https://help.tableau.com/current/pro/desktop/en-us/maps.htm https://help.tableau.com/current/pro/desktop/en-us/maps_howto_filled.htm https://help.tableau.com/current/pro/desktop/en-us/marks_markproperties_color.htm