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Functions and Triggers: Scalar UDF Inlining, Inline TVFs, Multi-Statement TVFs and Trigger Pitfalls

A scalar UDF that isn't inlined runs as a separate module per row: in a query over 17,359 orders the function was called 34,718 times, 365,498 logical reads never showed up in STATISTICS IO, and the plan couldn't go parallel. SQL Server 2019 inlining, is_inlineable, inline TVFs versus the fixed 100-row MSTVF estimate and interleaved execution, the single-row trigger assumption, EF Core's OUTPUT restriction and temporal tables for auditing, measured.