Data blending is a technique by which you can combine the data from multiple sources, and these sources can be anything like text, csv, excel file or can be a server like MySQL, SQL server, Oracle etc. Blending of data gives additional information from secondary data source along with primary data source during the visualization.
In joins they merge the data in a single file but in data blending, it keeps both the data sources separately one act as primary and rest will act as secondary data sources. It combines the information from these two sources and displays the information together, However data sources are not merge together. So as a result data blending act as a left join but on an aggregated level.
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