Cursors: The Hidden Performance Problem

Michael Swart notes that cursor performance can be hidden from monitoring tools:

The OPEN statement is missing from sys.dm_exec_query_stats. I want to demonstrate that.

There are a few workarounds, and Michael even provides us a handy table, so read the whole thing.

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VARCHAR Size And Memory Grant Estimates

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Visualizing Hash Match Joins

Bert Wagner continues his series on visualizing physical join operators: Hash Match joins are the dependable workhorses of physical join operators.While Nested Loops joins will fail if the data is too large to fit into memory, and Merge Joins require that the input data are sorted, a Hash Match will join any two data inputs […]

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