Left joins with a record

Left connection or very good use, is the first use not very skilled.

var leftList = from spider in spideResults
join upload in mydataResults on spider.SiteName equals upload.SiteName
into data
from myData in data.DefaultIfEmpty()
select new 
{
    spider,
    upload = myData
};

into meaning is to link out the result in the specified container, and then finally to see what results come out from grammar in it.

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