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What difference does .AsNoTracking() make?
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Can we get the same benefits for anonymous classes in select query, such as context.Users.Select(u=> new { Name = u.Name })? Thanks.
– Dilhan Jayathilake
Feb 6 '17 at 23:33
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When and why are database joins expensive?
...s back to mitigating the size of the working set. Joins involving properly selected keys with correctly set up indexes are cheap, not expensive, because they allow significant pruning of the result before the rows are materialised.
Materialising the result involves bulk disk reads which are the mo...
How to kill/stop a long SQL query immediately?
...uted and is suspended, and found that there are many instances of the same SELECT SQL having the same SPID. When I try to execute the command KILL 114 - here 114 is the SPID value of my suspended query. I get the error shon below: Please guide. Msg 102, Level 15, State 1, Line 2 Incorrect syntax...
MySQL join with where clause
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You need to put it in the join clause, not the where:
SELECT *
FROM categories
LEFT JOIN user_category_subscriptions ON
user_category_subscriptions.category_id = categories.category_id
and user_category_subscriptions.user_id =1
See, with an inner join, putting a claus...
Convert Existing Eclipse Project to Maven Project
...mport an existing Eclipse project. Rather, it gives the user an option of selecting dependencies, etc., which may be difficult if the user doesn't have much experience with Maven.
– Kaleb Pederson
Mar 15 '10 at 18:58
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How to convert an IPv4 address into a integer in C#?
...actually checks the endianness, here goes:
byte[] ip = address.Split('.').Select(s => Byte.Parse(s)).ToArray();
if (BitConverter.IsLittleEndian) {
Array.Reverse(ip);
}
int num = BitConverter.ToInt32(ip, 0);
and back:
byte[] ip = BitConverter.GetBytes(num);
if (BitConverter.IsLittleEndian) {...
How to retrieve checkboxes values in jQuery
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You can also return all selected checkboxes value in comma separated string.
This will also make it easier for you when you send it as a parameter to SQL
Here is a sample that return all selected checkboxes values that have the name "chkboxName" in...
How can I create a self-signed cert for localhost?
... Services (IIS) Manager or simply inetmgr.exe. From there go to your site, select Bindings... and Add... or Edit.... Set https and select your certificate from the drop down.
Your certificate is now trusted:
share
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Get element inside element by class and ID - JavaScript
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Well, first you need to select the elements with a function like getElementById.
var targetDiv = document.getElementById("foo").getElementsByClassName("bar")[0];
getElementById only returns one node, but getElementsByClassName returns a node list...
Fastest way to extract frames using ffmpeg?
...actly which frames to extract, eg 1, 200, 400, 600, 800, 1000, try using:
select='eq(n\,1)+eq(n\,200)+eq(n\,400)+eq(n\,600)+eq(n\,800)+eq(n\,1000)' \
-vsync vfr -q:v 2
I'm using this with a pipe to Imagemagick's montage to get 10 frames preview from any videos. Obviously the frame numbers ...