Coalesce has two separate phases for running your DAG against your data warehouse.
Deployment is responsible for structural changes to your data warehouse. Deployment starts with a calculation of differences in metadata between what is currently deployed to the environment and what the newly desired configuration state is - typically performing column/table creation or editing. This usually involves executing DDL (Data Definition Language) SQL statements such as ALTER, CREATE, and DELETE.
Refresh is responsible for running the data transformations defined in your data warehouse metadata. This typically involves DML (Data Manipulation Language) SQL statements such as MERGE, INSERT, UPDATE, and TRUNCATE which will perform transformations on the actual data.
Updated about 2 months ago