Hi @Vigneshg G,
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
We would like to inform you that, as of now, vector similarity search is available in Azure SQL Database in preview. However, there hasn't been an official announcement regarding its availability in Azure SQL Managed Instance.
Microsoft typically rolls out new features to Azure SQL Database first, followed by Azure SQL Managed Instance. For the most current information, I recommend regularly checking the Azure SQL Managed Instance release notes and the Azure SQL Database blog for updates on feature releases.
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