Query execution time

[pl456]

I have a query based on several other queries that fetches data from a SQL server. When I first run the query it can take a minute to fetch the data however once it has ran once and I change the criteria it fetches the new data in seconds.

Does anybody know why this is? Please

 

[namliam]

Probably most of that is time to open the connection to the database, authorizing and what not...
Try opening the database and just opening a table or a quick small query first, that should take pretty long too...

 

[pl456]

I have small queries running on the database, they run fine. Just the initial running of this one????

 

[Atomic Shrimp]

It could be that something is being cached somewhere (either by the database engine or by something lower level in the OS or even the disk controller - and hopefully, properly so that it doesn't result in out of date information being returned)

Or it could be that one of the database components somewhere in there is having to create an optimisation scheme - maybe one that is discarded after a certain amount of idle time, but can be re-used if called upon within that time.

 

[pl456]

Any idea how I might locate/update/amend/improve the mythical file?