Increased NCI Key Size

Jos de Bruijn notes that non-clustered index keys may be larger in SQL Server 2016 and Azure SQL Database:

SQL Server 2016 and Azure SQL Database have increased the maximum size for index keys with nonclustered indexes. The new maximum key size for nonclustered indexes is 1700 bytes. The maximum key size for clustered indexes remains 900 bytes.

95-99% of the time, we don’t want to get anywhere near 900 bytes (much less 1700 bytes), but we all have that one edge case.

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