In Tableau, when we load data from the source then it comes with its data types. All fields from Source data will have a data type that reflects the kind of information stored in them. Once the data is loaded into Tableau, it automatically categories data into four data types namely String, Number, Boolean, and DateTime. In certain cases, Tableau misinterprets the data type that can be corrected manually by right-clicking on the column in Data Pan and selecting the Change Data Type.
The following two topics will be covered in this Tableau Tutorial.
- Tableau Data Types
- Tableau Data Terminology
We will go through each topic in the following section.
Tableau Data Types
Tableau stores source data in one of the four data types which are Number, String, Boolean, and DateTime. In case the source column value is not matching with these data types then Tableau manages it differently. In most cases, it will put the Nulll value in the column.
The following is the list of data types and their description which are supported in Tableau.
| Tableau Data Types | Description | Example |
|---|---|---|
| NUMBER | The Number data type can store either the integers or floating points data. It is suggested to round off the floating points data during calculation. | The example is 50, 23.89. |
| STRING | The STRING data type contains any number of zero or more characters. | 'Tableau Tutorial' |
| BOOLEAN | The BOOLEAN data type stores the TRUE and FALSE values. | TRUE, FALSE |
| DATE & DATETIME | The Date data types contain the date value that is automatically identified by Tableau, In case if we are using the string as a date then we need to inform Tableau by using the #. | "06/10/1990" "#27 Sept 1988" |
Tableau Data Terminology
The Tableau Data Terminology is used to identify the unique terms and definitions which are used in Tableau. These unique terms are frequently used in Tableau so it is important to know these teams.
The following is the list of most common terms used in Tableau.
| Tableau Unique Terms | Description |
|---|---|
| Workbook | The Tableau Workbook is the collection of one or more worksheets. It can also contain dashboards and stories. |
| Worksheet | The Tableau Worksheet is the place where you can build views. In worksheet in Tableau can connect with one data source. |
| View | The Tableau View is the representation of data in the form of a Dashboard or Worksheet. |
| Repository | The Tableau Repository store the workbooks in the My Documents folder. |
| Format Pane | The Tableau Format Pane is used to performing the formatting of the entire worksheet and it is available on the left side of the workbook. |
| Marks | The Tableau Marks show the visual of one or more rows in source data. The types of Marks can be square, line, Bar, etc. |
| Packaged workbook | The Tableau Packaged workbook is usually created in the Tableau Desktop or Tableau Server and contains the workbook and related local copies of the data source. |
| Data source | The Tableau Reader is connected to the Data Source which can't be changed in Tableau Reader. |
| Filter | The Tableau Filter is used to restricting the data that will be shown in the view. An example of a filter is the Gender column where we want to show only female value. |
| Dashboard | The Tableau Dashboard consists of multiple views on a single page. It is helpful where we are performing the comparison of a variety of data. |
| Cross-tab | The Tableau Crosstab is a text table that is used to present the associated numbers of dimension members. |
| Alias | The Tableau Alias is another name that can be assigned to a field. |
| Bin | The Tableau Bin represents the groups of measures that are defined by the user in the Data source. |
| Bookmark | In Tableau a single worksheet can be saved as Bookmark. Once the Bookmark is saved the Tableau creates a worksheet snapshot. By using the Bookmarks menu the Bookmarks are accessible from any of the workbooks. |
| Calculated Field | In Tableau, Calculated Fields are the ones that are created post applying the formula on the existing fields. |
| Dimension | In Tableau, the Dimension holds the categorical data fields that can't be aggregated. An Example of Dimension data is a date, Customer date of birth, Customer name, and so on. |
| Extract | To perform the analysis and performance comparison the Tableau Extracts are used. It is offline data and can be created by defining the filters and limits. |