面试题与答案

A Live connection directly queries the data source in real-time, while an Extract creates a snapshot of the data that is stored in Tableau's proprietary format (.hyper) for faster performance.

Data can be filtered in Tableau using various techniques such as Quick Filters, Context Filters, and Top N filters. Users can also create calculated fields for more advanced filtering.

Tableau Prep is a data preparation tool that allows users to clean, shape, and combine data for analysis in Tableau. It helps in preparing data by handling tasks like cleaning, splitting, and aggregating data.

To create a dual-axis chart, drag a second measure to the right of the existing axis. Then, right-click on the second axis and select 'Dual Axis.' This allows for the comparison of two measures with different scales on the same chart.

To create a map in Tableau, drag a geographical dimension (like Country or State) to the Rows or Columns shelf. Tableau will automatically recognize the geographical data and generate the map. You can then drag measures to the color or size shelf for further customization.

Data blending in Tableau is the process of combining data from multiple data sources in a single view. It is often used when the data required for analysis comes from different sources, and a relationship between the sources needs to be established.

To create a calculated table, you can use the Data pane. Right-click on a blank space in the Data pane, select 'Create Calculated Table,' and define the calculations and columns you need. This feature allows you to create tables based on calculated expressions.

Tableau Server is a platform that allows organizations to publish, share, and collaborate on Tableau content. It provides a centralized location for storing and managing Tableau workbooks and dashboards, making it easier for users to access and interact with the data.

Data refresh in Tableau Server can be scheduled using the 'Refresh Schedules' option. Admins can set up schedules to refresh extracts at specified intervals, ensuring that the data remains up-to-date for users accessing Tableau Server.

The Pages shelf in Tableau is used for creating animated visualizations over time. It allows users to analyze how data changes over a specified dimension (e.g., time) by creating a series of static visualizations that can be viewed sequentially.