Can you explain the difference between the MERGE and APPEND statements in SAS?

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Understanding the Difference Between the MERGE and APPEND Statements in SAS

When working with SAS, it is important to understand the distinction between the MERGE and APPEND statements. The focus keyword for this discussion is "MERGE and APPEND statements in SAS."

The MERGE statement is used to combine datasets by matching the values of one or more variables in each dataset. This results in a single dataset containing information from both source datasets based on the specified match criteria. The MERGE statement creates a new dataset with observations that have matched keys from the source datasets.

On the other hand, the APPEND statement is used to combine datasets by appending the observations from one dataset to another. Unlike the MERGE statement, the APPEND statement simply stacks the observations from one dataset below the observations in another dataset, creating a larger dataset without any matching criteria.

In summary, the key difference between the two statements lies in how they combine datasets. The MERGE statement combines datasets based on matching criteria, while the APPEND statement simply appends observations one after another.

By understanding the distinction between the MERGE and APPEND statements in SAS, users can effectively manipulate and merge datasets to meet their analytical needs.