SQL Server tuning: SET STATISTICS profile on

After setting the SET statistics profile, you will return to the Execution plan table, through which you can understand the process of statement execution and understand if SQL Server chooses the correct execution plan to determine the tuning direction!

1. Returns the table field description:

Rows: The actual number of rows returned in each step of the execution plan

Executes: number of executions per step of the execution plan

Stmttext: The specific content of the execution plan, each step has its own execution content, and the result is returned, of course, each time, will spend the system resources (time CPU memory)

Estimaterows:sql Server estimates the number of rows that are returned per step, and we often compare the values of estimaterows with rows to confirm that SQL Server is estimated to be accurate

Estimateio:sql Server estimates the I/O resources spent per step execution

Estimatecpu:sql server estimates the CPU resources that are spent in each step of execution

Totalsubtreecost:sql Server calculates the cost of each step of the execution plan based on ESTIMATECPU and Estimateio, which includes the sum of both itself and all subtree execution plans under the tree .

Warnings:sql Server Estimated Warning (example: a step execution failed to find statistics support SQL Server estimate)

Parallel: Whether to use a parallel execution plan

SQL Server tuning: SET STATISTICS profile on