Comparing SQL Execution Plan Estimated Rows and Actual Rows is a good way of identifying potential hotspots. Differences in the numbers can mean statistics are out of date or code is written whereby the Optimizer can’t predict the row count.
How to troubleshoot a slow running query - SQL Server DBA
A common query tuning mistake is to compare the Estimated Rows and the rows column on the Execution Plan output. The correct method is to multiply Estimated Rows by Estimated Executions and compare to Actual Rows.
(Estimated Rows * Estimated Executions ) – Rows
All three columns are found on the STATISTICS PROFILE output. An example of creating the output is in this example
--an example of executing a stored procedure SET STATISTICS PROFILE ON GO exec "mystored_procedure";1 '1001' GO SET STATISTICS PROFILE OFF
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SQL Server Query Optimizer and Statistics - SQL Server DBA
SQL Server - Find last time STATISTICS updated - update statistics