Tableau can connect to a wide range of data sources, including Excel files, SQL databases, and cloud-based services like Google Sheets. This flexibility allows Tableau to integrate various data types and sources for visualization.
A left join would include all records from the “left” table (customer orders) and only the matching records from the “right” table (customer information). This approach ensures that all orders appear, even if they don't have corresponding customer details.
Data blending is used when combining data from different sources (e.g., different servers or types). Unlike joins, which combine data within the same data source, blending enables you to analyze data from diverse sources by linking on common fields.
Using a data extract with a subset of the data (such as a filtered selection) helps optimize performance by reducing the data Tableau has to process. This approach also enables faster loading and interaction, especially with large datasets.
Data extracts in Tableau allow offline analysis, enabling users to analyze data without a live connection, which can be resource-intensive. Extracts are especially useful for improving performance when working with large datasets.
