Tableau TDS-C01 Practice Test - Questions Answers, Page 7

This is true, indeed!

The LEFT JOIN keyword returns all records from the left table (table1), and the matched records from the right table (table2). The result is NULL from the right side, if there is no match.

You don't need to know ANY programming language to use quick table calculations!

Follow along with the steps below to learn how to apply a quick table calculation to a visualization:

1) Open Tableau Desktop and connect to the Sample-Superstore data source, which comes with Tableau.

2) Navigate to a new worksheet.

3) From the Data pane, under Dimensions, drag Order Date to the Columns shelf.

4) From the Data pane, under Dimensions, drag State to the Rows shelf.

5) From the Data pane, under Measures, drag Sales to Text on the Marks Card.

6) From the Data pane, under Measures, drag Profit to Color on the Marks Card.

7) On the Marks card, click the Mark Type drop-down and select Square.

The visualization updates to look like this:

Apply the quick table calculation

1) On the Marks card, right-click SUM(Profit) and select Quick Table Calculation > Moving Average.

Note: You can only perform quick table calculations on measures in the view.

A delta symbol appears on the field to indicate that a quick table calculation is being applied to the field. The colors in the visualization update to show the moving average of profit across the years.

Since Sales is a measure, it can easily be depicted via size.

To drill down and change the level of detail, Country is the correct choice since it will contain STATE. We can then depict the various states by different shapes such as circle, square etc.

Finally, the Profit can be depicted via a color! Eg - Red for poor and green for excellent profits!

When using a Blend, the primary data source appears with a BLUE tick-mark and the secondary data source appears with a ORANGE tick-mark.

See below:

THIS IS A VERY IMPORTANT QUESTION

To answer this question, you need to understand Tableau's Order of Operations. See below and remember this always:

Yes! To concatenate fields, they must be of same data type. However, there is a workaround which we can use - Type casting. See below:

Here, State and City are Strings, but Postal Code? Nope. It's an Integer. So we can simply use the STR() function to convert it into a String, and hence the entire equation becomes valid!

Since we need to focus on 1 country -> Japan, let's filter on it first as follows:

1) Drag Country to the filter shelf, and choose only Japan. Click OK.

2) Read the Question Carefully, we need to break down the visualisation by Region, then by Country, and then by State. So let's do that:

Drag Region to the column shelf, followed by Country. Drill down into Country to include states as well.

Then drag Quantity to the Row Shelf, and change the Aggregation to AVERAGE.

The following is our visualisation:

Now that you think of it, EVEN IF YOU REMOVE THE REGION, THE ANSWER REMAINS THE SAME. Such elements will be present in the actual exam too, just to make the question sound a little difficult, but actually it is pretty straightforward :)

VERY IMPORTANT QUESTION FOR THE EXAM, PAY ATTENTION

1) To find the number of days between order date and shipping date, we will make use of a calculated field:

In the data pane, click on the dropdown arrow, and choose create calculated field.

Let's name this calculated field 'ShippingDelay' (you can name it anything you want :) )

2) Use the DATEDIFF() function, and pass it the arguments as follows:

'day' depicts that we want to calculate the number of DAYS between the two dates. The first argument is 'start_date' which is the ORDER_DATE (day the order was placed), the second argument is 'end_date', which is the SHIP_DATE (date the order was shipped). So by subtracting as follows: SHIP_DATE - ORDER_DATE, we can find the delay in shipping.

Click OK.

3) You should now have a new measure as follows:

4) Phew! The hard part is done! Now let's filter by Market to include only LATAM:

5) Drag Country to the view, and the new calculated field 'ShippingDelay' to SIZE on the Marks Shelf as follows:

*You can also click on Show Text Labels to be sure that you're choosing the Largest value*

Clearly, Mexico has the highest Shipping Delay!