Data Blending is a most powerful feature in Tableau. Data Blending is a method for combining the data i.e. suppose there is a common data in multiple data sources, we want to analyze the data together in a single view.
For example, consider you have transactional data stored in Salesforce and target data stored in Excel worksheet. Now you want to combine the data stored in different databases, and the quality of the data captured in each table is different in both data sources, For this process data blending is the best way to mix the data.
Learn more about this technology Tableau Online Training in this overview
By the following condition Data Blending is very useful:
Mix the data from a various database that are not bear by cross-database joins.
Cross-database joins does not support the connection to the cube (Example Essbase). In this situation set up a separate data source for the data you want to analyze, and then in the next process, we want to use data blending to mix the data in a single sheet.
By using following conditions we can use data blending instead of joins:
Data needs cleaning.
After joining your tables does not match with each other, set up a data source for every table, make changes if necessary (change column data types, create groups, change the column name, use calculations, so on) after this process is completed use blending to join (or) combine the data.
Joins are handled by the database, which can allow joining to hold some of the database natives capabilities. If you are working with a large data, joins put a tension on the database and seriously affect the performance. In this situation, data blending can help. Tableau manages to combine the data after the data is formed when there are fewer data to mixing it can obviously improve the performance.
A precondition for data blending:
If you want to use data blending your data must reach the below conditions.
Data blending needs a primary data source and minimum one secondary data source. Suppose you appoint a primary data source, it works as the main data source. And any other upcoming data table or data source that you can use on a sheet are used as a secondary data source. In Secondary data source, only columns are the corresponding matches in the primary data source appear in the view.
From the above description, you nominate the quota as the primary data source and transactional data as a primary data source. Multidimensional data sources are used as the primary data source and Multidimensional data sources can’t use as a secondary data source.
Explain the relationship between the primary data source and secondary data source.
After the nominating primary and secondary data source, you must point the dimensions between the two data sources. This dimension also knows as linking field. Tableau notice that when the field from the primary data source and this also exists in the secondary data source it indicates potential linking and Tableau creates a relationship between two fields and shows the link icon.
Difference between joins and data blending
The join is performed with respect to aggregation this is the main difference.
Depending on our requirements we can change the joinings”Left join”,”Right join”, “Inner join”, “Full Outer join”. Suppose you can use a left join to combine data, this query is sent to the database where it can be performed. By using left join return all rows present in the left table and if any other row present in the right table that has a corresponding match in their left table.
Suppose you can use a data blending to mix the data, this query is sent to the database for each and every data source used in the sheet. The views use the aggregated row from the secondary data source, the right table, and all rows from the primary data source, left table, based on the dimensions of the linking field.
Anybody can learn tableau if you have a technical degree with basic coding knowledge. Trainers of OnlineITGuru will teach every topic they are real-time experts. Get more Knowledge join OnlineITGuru for mastering the Tableau Online Course Bangalore.