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How to get the index of an element in an IEnumerable?
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extensions with overloads like Select((x, i) => ...) seem to imply that these indexes should exist
– Michael
Mar 19 '14 at 16:05
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Delete sql rows where IDs do not have a match from another table
...HERE f.id IS NULL
Using NOT EXISTS:
DELETE FROM BLOB
WHERE NOT EXISTS(SELECT NULL
FROM FILES f
WHERE f.id = fileid)
Using NOT IN:
DELETE FROM BLOB
WHERE fileid NOT IN (SELECT f.id
FROM FILES f)
Warning
Whenever possible, per...
Connect to Amazon EC2 file directory using Filezilla and SFTP
...SFTP, Click "Add key file”
Browse to the location of your .pem file and select it.
A message box will appear asking your permission to convert the file into ppk format. Click Yes, then give the file a name and store it somewhere.
If the new file is shown in the list of Keyfiles, then continue t...
How to disable the highlight control state of a UIButton?
I've got a UIButton that, when selected, shouldn't change state when being touched.
The default behaviour is for it to be in UIControlStateHighlighted while being touched, and this is making me angry.
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Hidden Features of MySQL
...that has an integer type,
you can also refer to the column as "_rowid" in SELECT statements.
In MySQL, the name of a PRIMARY KEY is PRIMARY
Currently, only InnoDB (v5.1?) tables support foreign keys.
Usually, you create all the indexes you need when you are creating tables.
Any column declared...
Database development mistakes made by application developers [closed]
... the log output from Hibernate and you'll see all the queries begin with:
SELECT DISTINCT ...
This is a bit of a shortcut to ensuring you don't return duplicate rows and thus get duplicate objects. You'll sometimes see people doing this as well. If you see it too much it's a real red flag. Not...
How to do multiple line editing?
...
Press alt + shift + A to Toggle block selection (Toggle block / column selection in the current text editor), this will let you write vertically in eclipse, then you can easily do this.
Go to Window->Preferences.
Find for binding in text box surrounded b...
How do I break a string across more than one line of code in JavaScript?
...n your example, you can break the string into two pieces:
alert ( "Please Select file"
+ " to delete");
Or, when it's a string, as in your case, you can use a backslash as @Gumbo suggested:
alert ( "Please Select file\
to delete");
Note that this backslash approach is not necessarily preferr...
Distinct not working with LINQ to Objects
...ey were hit during the foreach loop. This is because the var temp = books.SelectMany(book => book.Authors).Distinct(); returns an IEnumerable, meaning that the request is not executed right away, it is only executed when the data is used. If you would like an example of this firing right away, ...
string.Join on a List or other type
...le<T>)
If you can't upgrade, you can achieve the same effect using Select and ToArray.
return string.Join(",", a.Select(x => x.ToString()).ToArray());
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