What is 'merge join' in SAP EIM-DI-DF - SAP BusinessObjects Data Federator?

merge join - Overview

• Component: EIM-DI-DF

• Component Name: SAP BusinessObjects Data Federator

• Description: An operation used in data federation where two large tables of data are sorted before they are joined, in order to reduce the time it takes to join the tables.

merge join - Details

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  Key Concepts: 
  Merge join is a type of join operation used in SAP BusinessObjects Data Federator (EIM-DI-DF). It combines two data sources into one by matching the values of one or more columns from each source. The result is a single table with all the data from both sources. 
  
  How to use it: 
  To use merge join, you must first define the join condition. This is done by specifying the columns from each source that should be matched. Then, you can select the columns from each source that should be included in the resulting table. Finally, you can specify any additional conditions that should be applied to the data before it is merged. 
  
  Tips & Tricks: 
  When using merge join, it is important to make sure that the data types of the columns being matched are compatible. If they are not, then the join may not work as expected. Additionally, it is important to make sure that all of the columns being matched have unique values, otherwise duplicate rows may be created in the resulting table. 
  
  Related Information: 
  Merge join is similar to inner join and left outer join operations, but it has some key differences. Inner join only includes rows where there is a match between both sources, while merge join includes all rows from both sources regardless of whether there is a match