+1 for adding such flag. Not sure about disabling it by default. Current behavior may be redundant for many cases, but it looks consistent and sensible for users who use it for the first time.
On Wed, Jan 28, 2015 at 10:21 AM, Alexey Kuznetsov <[email protected]> wrote: > Could we print some warnings / performance suggestions in case of long > iterations over existing results? > > On Wed, Jan 28, 2015 at 2:11 PM, Valentin Kulichenko < > [email protected]> wrote: > > > Currently, when continuous query is executed, it first iterates over > > existing results before processing continuous updates. This iteration can > > take a lot of time and not always needed. > > > > Imagine simple scenario: > > > > - Load initial data from DB to cache; > > - Register continuous query for further updates that will happen while > > application is running; > > - Run the application. > > > > In most cases notifications on initial data are not needed, but you get > > them regardless of whether you registered query before or after data > > loading. > > > > I think we should add a flag on continuous query that allows to enable or > > disable this behavior. Also I think that it should be disabled by default > > because I really can't imaging a use case when you need to iterate > through > > the whole cache. Also it's not obvious what is happening in this case - > if > > user was not attentive enough reading the documentation and there is a > lot > > of data, he may think that query simply hanged during registration > process. > > > > Thoughts? > > > > > > -- > Alexey Kuznetsov > GridGain Systems > www.gridgain.com >
