Hi @dishasharma ,
Both are completely different activities with different purpose.
Enrichment is used to add additional data, create a link between temporary table and database schema and many (refer here for further details)
Whereas change dimension is used to change the targeting dimension. Let's say if you have broadLogRcp as your targeting dimension, and you want to change the targeting dimension to nms:Recipient, you can do it by using change dimension (refer here for more details)
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