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Data Setup

Why Tableau?

People use Tableau for its exploration and visualization capabilities, as well as its data analytics capabilities. Tableau’s data interface is easy to navigate, allowing users to scroll through and get a sense of their data before and during visualization development.

Setting Up a Tableau Public Account

A Tableau Public account allows users to build an online portfolio, connect with other Tableau users and potential employers, and store work publicly or privately. It’s one of the most important tools (if not THE most important tool!) for analysts and developers looking to showcase their Tableau visualizations.

Loading data

With Tableau Public, data can be loaded from a local file and modified in Tableau for readability. Text file refers to a .csv file and Microsoft Excel refers to any file with an .xls or .xlsx extension

Join, Unions, and Relationships

In Tableau, data from multiple sources can be automatically or manually “joined” using the Relationship function. As long as two columns contain the same data, they can be used to join two separate sheets – if the names don’t match, the user can manually designate the join.

Dimensions and Measures

In Tableau, ​​dimensions contain qualitative (descriptive) information. Measures contain quantitative (calculable) information, including any numbers that can be summed, averaged, or counted. Length, sales totals, and weight are examples of measures. Name, species, and year are examples of dimensions.

Sums, Counts & Aggregates

In Tableau, measures can be aggregated using integrated functions for sum, mean, median, count and count_distinct, among others. Sum adds all the values in a given field. Mean takes the average of all values in a given field. Median takes the median (middle) value of a given field. Count returns the number of values (rows) in the field. Count distinct returns the number of unique values in the field.


In Tableau, filtering data helps developers work more quickly with large volumes of data. Filtering also makes visualizations more readable and add a valuable layer of user-interactivity. Filters can also be used to remove null values.

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