In the following example we again specify the server using “-S” but we also pass the “-Q” parameter which allows us to pass a query in on the command line that will be executed as soon as the connection completes. Note that after the query completes sqlcmd will exit and put you ...
Parameterization is a technique used to optimize query performance by reusing query execution plans. When a parameterized query is executed, SQL Server can reuse the query execution plan instead of creating a new one each time the query is executed. This can significantly improve query performance, ...
The query plan shows a Nested Loops from EMPLOYEE to full table scan DEPARTMENT, it is the main problem of the entire query plan, the reason is the SQL Server cannot resolve this OR conditions ”a.emp_id=b.dpt_manager or a.emp_salary=b.dpt_avg_salary” by other join operations. Let...
Performance is a big deal. No matter if we’re talking about applications in which users click buttons to display data or if we’re writing a query directly into let’s saySQL Server Management Studio(SSMS). Nobody likes to click a button, go get a coffee, and hope the results are re...
There are several solutions to deal with parameter sniffing as below: Use EXEC () to run dynamic SQL statements. Use local variables. Use query hint in the statement to specify the execution plan. A:With Recompile B:Specify the Join operation ({ LOOP | MERGE | HASH} JOIN)(not reco...
Determine user activity to find out what queries users are issuing and who is connecting to SQL Server. Troubleshoot problems. Test applications. In This Section This section contains information about how to use SQL Server performance monitoring and tuning tools. ...
SQL Server to execute the query. Nothing was changed between executions so most of the values are the same or very similar. As changes are made to the query or to the schema of the database the query can be executed again and the values compared to see if there is an improvement or ...
it is more often than not caused by a bad query. While everyone always hopes to recover through some quick config tuning, the real fix is to identify and fix the problem query. Sure, we can generally alleviate some pain by throwing more resources at the server. But this is almost always...
The fine-tuning of a T-SQL query is an important concept. The fundamental thing to understand is how well we can write T-SQL queries and implement indexes, so that the SQL optimizer can find an optimized plan to do what we wanted it to do. With every new release of SQL Server, we ...
description => 'Task to tune a query'); DBMS_SQLTUNE.EXECUTE_TUNING_TASK(task_name => 'test_sql_tuning_task1'); END; / 2、SQL id format: DECLARE my_task_name VARCHAR2(30); my_sqltext CLOB; BEGIN my_task_name := DBMS_SQLTUNE.CREATE_TUNING_TASK(sql_id => 'b3uaak09jfaxc',...