SQL Server 2019: working with Deadlocks When Using Indexed Views in High-Concurrency Environment
I am experiencing deadlocks in SQL Server 2019 when multiple transactions are trying to access an indexed view simultaneously. The indexed view is used to aggregate data from a large table and is essential for performance in our reporting queries. I have set the view with a clustered index, and I am trying to select from this view while concurrently updating the base tables involved in the view. The deadlock behavior I receive is: ``` Transaction (Process ID 65) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction. ``` Here’s a simplified version of the T-SQL code in use: ```sql CREATE VIEW dbo.AggregatedData WITH SCHEMABINDING AS SELECT Column1, SUM(Column2) AS Total FROM dbo.LargeTable GROUP BY Column1; GO CREATE UNIQUE CLUSTERED INDEX IX_AggregatedData ON dbo.AggregatedData (Column1); GO -- Upsert operation on the base table BEGIN TRANSACTION; UPDATE dbo.LargeTable SET Column2 = Column2 + 100 WHERE SomeCondition; INSERT INTO dbo.LargeTable (Column1, Column2) VALUES ('NewValue', 100); COMMIT TRANSACTION; ``` I’ve tried implementing `WITH (NOLOCK)` hints for my select statements but this leads to inconsistent data being read, which is not acceptable for our reporting requirements. I've also reviewed the transaction isolation levels and experimented with `READ COMMITTED SNAPSHOT` but it hasn't resolved the deadlock scenario. Any suggestions on how to minimize or eliminate these deadlocks while still providing timely access to the indexed view? Is there an optimal way to structure the queries or transactions to avoid these conflicts? This is part of a larger REST API I'm building.