dataSource.filter running twice

[Bridge24]

In our app, we are using "custom filtering", as we set our own function in the "operator" property of the filter.

I found, that, every operator is called twice.  If I have 10 rows to filter, and 1 operator set for 1 specific filter, it runs 20 times, from 1 to 10, and again from 1 to 10.

Steps to reproduce: 

http://dojo.telerik.com/@foxontherock/EfOyiwIS

After some investigation, I found this:

In your "query" function, you run this: 

(copied from the minified version + chrome prettyPrint in F12)
result = this._queryProcess(this._data, this._mergeState(options)); 

The filter is applied.

Then, a few lines later, that:

this._aggregateResult = this._calculateAggregates(this._data, options);

And, from that line, the whole filtering is applied again.

When we have only a few lines to filter, it's quick. 

But with 5000 rows of 10 filters per row, running it twice is a good difference in cpu, memory and time!

You can look at my dojo sample, it's easy to reproduce.

 

[Stefan]

Hello, Daniel,

Thank you for the example and all of the details.

This occurs because the filter is called again when the aggregates are calculated.

1) https://github.com/telerik/kendo-ui-core/blob/master/src/kendo.data.js#L1726
2) https://github.com/telerik/kendo-ui-core/blob/master/src/kendo.data.js#L3628

I will forward this to the developers' team to check if we can only execute the second filter if there are aggregates or grouping.

Regards,
Stefan
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