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With MySQL, how can I generate a column containing the record index in a table?
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You may want to try the following:
SELECT l.position,
l.username,
l.score,
@curRow := @curRow + 1 AS row_number
FROM league_girl l
JOIN (SELECT @curRow := 0) r;
The JOIN (SELECT @curRow := 0) part allows the variable initiali...
How to select html nodes by ID with jquery when the id contains a dot?
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@Tomalak in comments:
since ID selectors must be preceded by a hash #, there should be no ambiguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The correct...
Is there a C# type for representing an integer Range?
...sult = new List<int>();
string[] lines = input.Split(new char[] {';', ','});
foreach (string line in lines)
{
try
{
int temp = Int32.Parse(line);
result.Add(temp);
}
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Fastest way to determine if record exists
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SELECT TOP 1 products.id FROM products WHERE products.id = ?; will outperform all of your suggestions as it will terminate execution after it finds the first record.
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View array in Visual Studio debugger? [duplicate]
...lso use a cast in the debug view. If pArray is of type void* you can type (char*) pArray, 10 which will display the content of the array interpreted as char.
– VoidStar
Aug 15 '13 at 9:26
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Best way to create unique token in Rails?
...ittle bit of code in his Railscast on beta invitations. This produces a 40 character alphanumeric string.
Digest::SHA1.hexdigest([Time.now, rand].join)
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how to listen to N channels? (dynamic select statement)
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You can do this using the Select function from the reflect package:
func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool)
Select executes a select operation described by the list of cases. Like
the Go select statement, it bl...
Why is enum class preferred over plain enum?
...this is usually an int. Also each enumerated type shall be compatible with char or a signed/unsigned integer type.
This is a wide description of what an enum underlying type must be, so each compiler will take decisions on his own about the underlying type of the classic enum and sometimes the resu...
How to check whether a file is empty or not?
... my_file.seek(0) #ensure you're at the start of the file..
... first_char = my_file.read(1) #get the first character
... if not first_char:
... print "file is empty" #first character is the empty string..
... else:
... my_file.seek(0) #first character wasn't empty, retu...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...