To perform a merge in SAS to combine matching records into one dataset, non-matching records from the left-most dataset into a second dataset, and non-matching records from the right-most dataset into a third dataset, you can use the MERGE statement in conjunction with the IN= option. Here is an example code snippet on how to achieve this:

```html

Merge in SAS Example

To perform the merge operation in SAS:

data combined_dataset (keep=common_variables);
   merge left_dataset(in=left) right_dataset(in=right);
   by common_variable(s);
   if left and right then output matched_records;
   else if left then output left_non_matching;
   else output right_non_matching;
run;

Explanation:

• left_dataset and right_dataset are the two datasets to be merged.
• common_variable(s) are the variables used to match records.
• matched_records will contain the matching records.
• left_non_matching will contain non-matching records from the left dataset.
• right_non_matching will contain non-matching records from the right dataset.

```

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