Column-level encryption (CLE) helps customers implement fine-grained protection of sensitive data within a table (server-side encryption). With CLE, customers gain the ability to use different protection keys for columns in tables with each key having its own access permissions. The data in CLE enforced columns is encrypted on disk (and remains encrypted in memory) until the DECRYPTBYKEY function is used to decrypt it.
This feature applies to dedicated SQL pools in Azure Synapse Analytics.
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