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Always Encrypted vs Always Encrypted with secure enclaves

PieterVanhove's avatar
PieterVanhove
Icon for Microsoft rankMicrosoft
Jun 06, 2024
Introduction Encryption is a vital technique for protecting sensitive data from unauthorized access or modification. SQL Server and Azure SQL Database offer two encryption technologies that allow y...
Updated Jun 05, 2024
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azure sql
azure sql security
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Francesco_beqom's avatar
Francesco_beqom
Brass Contributor
Jul 22, 2024

Thank you PieterVanhove , this is more clear now. I was just having a look at the https://learn.microsoft.com/en-us/sql/relational-databases/security/encryption/always-encrypted-enclaves?view=sql-server-ver16#known-limitations: 

  • No Clustered indexes, no PK or FK or unique key constraints: What if I have those in place right now? Do I need to remove all those before I enable secure enclave? Or will those be dropped as soon as I enable enclave? 
  • Only nested loop joins are supported: this will significantly slow down the performances. Does it means that all hash joins and merge joins will become nested loop joins automatically? Or they will just fail? 
  • Escape character in LIKE operator: all WHERE column_directory LIKE '%D:\user\franc\%' will fail. This is heavy. This means we can give up using the LIKE operator in mostly XML, JSON, etc...