XDataWebDataset and querystring Filter

Hi i need to 'select' a substring with filter like this :

Format('$filter=(Desc_Art SUB ?? ''%s'')',[Substring]);

How i can do this by filter ?

using XDataWebDataset.Filter what is the difference ?
can i use SQL dilect to select records server side ?

thx

You can use functions Contains, StartsWith and EndsWith.

For example:

Format('$filter=(Contains(Desc_Art, ''%s'')',[Substring]);