問題文
A data analyst adds a PRIMARY KEY on the customer_id column of a dimension table that is reloaded nightly from an upstream system. The next morning the table contains two rows with the same customer_id. What explains this result?
選択肢
- The duplicate exists only in the metadata cache and will disappear the next time the table is clustered.
- The nightly load used COPY INTO, and key enforcement applies only to rows inserted with the INSERT statement.
- The primary key was created without the ENFORCED keyword, which is required in advance for Snowflake to reject duplicate values.
- Snowflake records the primary key as metadata but does not enforce it, so the duplicate row was accepted by the load.