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Equivalent of SQL ISNULL in LINQ?

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In SQL you can run a ISNULL(null,'') how would you do this in a linq query? I have a join in this query: var hht = from x in db.HandheldAssets join a in db.HandheldDevInfos on x.AssetID equals a.DevName into DevInfo from aa in DevInfo.DefaultIfEmpty() select new { AssetID = x.AssetID, Status = xx.Online }; but I have a column that has a bit type that is non nullable (xx.online) how can I set this to false if it is null? Since aa is the set/object that might be null, can you check aa == null ? ( aa / xx might be interchangeable (a typo in the question); the original question talks about xx but

jQuery check if Cookie exists, if not create it

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问题 I cannot get this code to work I must be missing something pretty simple. I am trying to check to see if a Cookie exists, if it does {do nothing} if it doesn't {create it}. I am testing the cookie by including an alert on a page. Basically I do not want the cookie to keep re-creating with a referral url, I am trying to grab only the FIRST referred URL. $(document).ready(function(){ if ($.cookie('bas_referral') == null ){ var ref = document.referrer.toLowerCase(); // set cookie var cookURL = $

Using ISNULL vs using COALESCE for checking a specific condition?

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I know that multiple parameters can be passed to COALESCE , but when you want to to check just one expression to see if it doesn't exist, do you use a default or is it a better practice to use ISNULL instead? Is there any performance gain between the two? onedaywhen This problem reported on Microsoft Connect reveals some differences between COALESCE and ISNULL : an early part of our processing rewrites COALESCE( expression1, expression2 ) as CASE WHEN expression1 IS NOT NULL THEN expression1 ELSE expression2 END . In [this example]: COALESCE ( ( SELECT Nullable FROM Demo WHERE SomeCol = 1 ), 1