I need to measure SPARQL query execution time. Could you please inform me what command I need to use for that? I am using Virtuoso.
Virtuoso 7 lets you get the compilation (query plan) and query execution time of a query using the profile function.
You can also enable general query logging and profiling using the prof_enable function.
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For tracked SQL function, hasura query is taking a lot of time but when it is executed from SQL directly it takes only few milliseconds to get the data. We are not able to figure out what is the actual problem as we are using Postgresql DB
We followed some steps to reduce the response time
Applying indexes on DB
Analysing the query plan to reduce the cost
Querying only a limited set of data to reduce the response size
We tried to run that query from SQL directly which only took few milliseconds but when when try to run from hasura query it took a lot of time for same parameters
I suspect that it is probably due to permissions that are being evaluated when you run the function through Hasura.
When you were analysing the query plan, did you also make sure that you were passing in roles to ensure that the plan captures any additional changes to the query that are required in order for the permissions to be evaluated?
I have a query and run it using SQL management studio. Usually, there is created one execution plan for a query in the studio. But sometimes I can catch up the duplicated execution plans for a single Query on the Azure SQL like below.
When I open the query from this plan I see the duplicated query. As if the copied query is pasted into the same query. The same in Query 1 and Query 2. See below.
Maybe someone knows why does this happen and how to avoid this behavior? How is that even possible?
P.S. Time of execution query was increased from 2 sec to 20 sec and more.
P.P.S. The warning in the Query 2
It could be that the queries were ran with different settings. I can notice that one has a warning and the other doesn't.
Reference:
https://blogs.msdn.microsoft.com/psssql/2014/04/03/i-think-i-am-getting-duplicate-query-plan-entries-in-sql-servers-procedure-cache/
I have a SQL query, first I analyzed the query by executing and it is taking less than 1 ms.
So I used the query in my spring boot app, and tried to execute it using
namedParameterJdbcTemplate.query(sqlQuery, params, new validationMapper());
but when I see the time, it is 19212ms.
Why this much time difference?
I am running Impala query on Hue. I want to know the execution time of each Impala query. I looked over different answers on the Internet, but I could not figure out.
impala service runs on 25000 port, there you can see all the queries and the time of execution. for quickstart node, example url is: quickstart.cloudera:25000/queries
I know, from whatever I've read, prepared statements are faster since pre-compiled cached version is used for recurring queries. My doubt is : Exactly where time is saved? I see, only the time taken in preparing a query could be saved. Even prepared statements have to do database search and so no time is saved there. Am I wrong?
That's correct. The time saved by using prepared statements is generally in the database engine planning/compiling the query.
The part of a "prepared query" that is prepared is the execution plan. The plan tells the database how to execute the query; which indexes to use, in which order. The execution plan also resolves any access rights.
Time is saved by building the execution plan once instead of for every query.