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CHECK constraint in MySQL is not working
...GER `test_before_insert` BEFORE INSERT ON `Test`
FOR EACH ROW
BEGIN
IF CHAR_LENGTH( NEW.ID ) < 4 THEN
SIGNAL SQLSTATE '12345'
SET MESSAGE_TEXT := 'check constraint on Test.ID failed';
END IF;
END$$
DELIMITER ;
Prior to MySQL 5.5 you had to cause an error, e.g. ca...
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...
jQuery - setting the selected value of a select control via its text description
I have a select control, and in a javascript variable I have a text string.
21 Answers
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Is String.Contains() faster than String.IndexOf()?
I have a string buffer of about 2000 characters and need to check the buffer if it contains a specific string.
Will do the check in a ASP.NET 2.0 webapp for every webrequest.
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Output data from all columns in a dataframe in pandas [duplicate]
...idth of your console.
Alternatively, you can change the console width (in chars) from the default of 80 using e.g:
pandas.set_option('display.width', 200)
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How to filter SQL results in a has-many-through relation
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Results:
Total runtimes from EXPLAIN ANALYZE.
1) Martin 2: 44.594 ms
SELECT s.stud_id, s.name
FROM student s
JOIN student_club sc USING (stud_id)
WHERE sc.club_id IN (30, 50)
GROUP BY 1,2
HAVING COUNT(*) > 1;
2) Erwin 1: 33.217 ms
SELECT s.stud_id, s.name
FROM student s
JOIN ...
Vim: faster way to select blocks of text in visual mode
I have been using vim for quite some time and am aware that selecting blocks of text in visual mode is as simple as SHIFT + V and moving the arrow key up or down line-by-line until I reach the end of the block of text that I want selected.
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How do I disable text selection with CSS or JavaScript? [duplicate]
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<div
style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;"
unselectable="on"
onselectstart="return false;"
onmousedown="return false;">
Blabla
</div>
...
Can I apply the required attribute to fields in HTML5?
How can I check if a user has selected something from a <select> field in HTML5?
13 Answers
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How to check if an option is selected?
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UPDATE
A more direct jQuery method to the option selected would be:
var selected_option = $('#mySelectBox option:selected');
Answering the question .is(':selected') is what you are looking for:
$('#mySelectBox option').each(function() {
if($(this).is(':selected')) ....