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What's wrong with nullable columns in composite primary keys?
...ow in a table: when a table has a primary key, you have a guranteed way to select any row from it.
A unique constraint does not necessarily identify every row; it just specifies that if a row has values in its columns, then they must be unique. This is not sufficient to uniquely identify every row...
Is it possible to embed animated GIFs in PDFs?
...mes by making a fake loop.
Open the Gif in Photoshop
View the timeline
Select all the instances and duplicate them (I did it 10 times)
Export as a MP4
Open up your PDF and go to TOOLS> RICH MEDIA>ADD VIDEO> then place the video of your gif where you would want it
A window comes up, be s...
How to use a switch case 'or' in PHP
...le switch(), and when I'm working in a C-ish language I really miss having Select Case, which is really a shorthand way of saying "there's a big block of if, else if, else-if... here".
– Stan Rogers
Oct 9 '10 at 7:50
...
How to delete a file from SD card?
...
File file = new File(selectedFilePath);
boolean deleted = file.delete();
where selectedFilePath is the path of the file you want to delete - for example:
/sdcard/YourCustomDirectory/ExampleFile.mp3
...
How to access random item in list?
... isn't repeated? Let's say I wanted to shuffle a deck of cards by randomly selecting one at a time, but obviously can't select the same card twice.
– AdamMc331
Sep 21 '14 at 5:26
7...
Improving bulk insert performance in Entity framework [duplicate]
... {
var e = entity;
table.Rows.Add(properties.Select(property => GetPropertyValue(property.GetValue(e, null))).ToArray());
}
// send it to the server for bulk execution
bulkCopy.BulkCopyTimeout = 5 * 60;
bulkCopy.WriteToServer(table);
...
Is there a way to do repetitive tasks at intervals?
...(5 * time.Second)
quit := make(chan struct{})
go func() {
for {
select {
case <- ticker.C:
// do stuff
case <- quit:
ticker.Stop()
return
}
}
}()
You can stop the worker by closing the quit channel: close(quit).
...
How to replace list item in best way
...a", "b");
// {"b", "b", "c", "d"};
var intEnum = intArray.Select(x => x);
intEnum = intEnum.Replace(0, 1);
// {0, 0, 1, 2, 3, 4} => {1, 1, 1, 2, 3, 4}
No code duplication
There is no need to type long linq expressions
There is no need for additional usings
T...
SQL Server Operating system error 5: “5(Access is denied.)”
...s ->
Double Click SQL Server (SQLEXPRESS) -> right click, Properties
Select Log On Tab
Select "Local System Account" (the default was some obtuse Windows System account)
-> OK
right click, Stop
right click, Start
Voilá !
I think setting the logon account may have been an option in the ...
Remove unused references (!= “using”)
...u get the the second result, you can then right mouse click the Reference, select Remove, and remove it from your project.
While you have to to this "manually", i.e. one reference at a time, it will get the job done. If anyone has automated this in some manner I am interested in hearing how it was...