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How to print third column to last column?
...e the same between all columns, but there have to be EXACTLY ONE delimiter character between columns. So if you are dealing with programs that align their output with delimiters, it is better to use awk.
– sknaumov
Aug 21 '12 at 12:40
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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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When should I use nil and NULL in Objective-C?
...ke a C pointer) in Objective-C. Like nil , NULL got no value nor address.
char *myChar = NULL;
struct MyStruct *dStruct = NULL;
So if there is a situation, when I need to check my struct (structure type variable) is empty or not then, I will use:
if (dStruct == NULL)
NSLog("The struct is emp...
maxlength ignored for input type=“number” in Chrome
...rch, password, tel, or url, this attribute specifies the maximum number of characters (in Unicode code points) that the user can enter; for other control types, it is ignored.
So maxlength is ignored on <input type="number"> by design.
Depending on your needs, you can use the min and max at...
How to declare a variable in MySQL?
...at has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BETWEEN @start AND @finish...
Is there an onSelect event or equivalent for HTML ?
I have an input form that lets me select from multiple options, and do something when the user changes the selection. Eg,
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How to disable text selection using jQuery?
Does jQuery or jQuery-UI have any functionality to disable text selection for given document elements?
13 Answers
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Best way to unselect a in jQuery?
What is the best way, using jQuery, to elegantly unselect the option?
15 Answers
15
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How do I check if a variable exists in a list in BASH
... give false positive if the user input contains regular expression special characters, for example x=.
– glenn jackman
Nov 9 '11 at 11:41
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How do I convert a double into a string in C++?
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// The C way:
char buffer[32];
snprintf(buffer, sizeof(buffer), "%g", myDoubleVar);
// The C++03 way:
std::ostringstream sstream;
sstream << myDoubleVar;
std::string varAsString = sstream.str();
// The C++11 way:
std::string varAsS...