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jQuery Validate Required Select
I am trying to validate html select element using jQuery Validate plugin. I set "required" rule to true but it always passes validation because zero index is chosed by default. Is there any way to define empty value that is used by required rule?
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How to order by with union in SQL?
Is it possible to order when the data is come from many select and union it together? Such as
8 Answers
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Reference alias (calculated in SELECT) in WHERE clause
The calculated value BalanceDue that is set as a variable in the list of selected columns cannot be used in the WHERE clause.
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C++及Windows异常处理(try,catch; __try,__finally, __except) - C/C++ - ...
...ss File_handle {
FILE* p;
public:
File_handle(const char* n, const char* a)
{ p = fopen(n,a); if (p==0) throw Open_error(errno); }
File_handle(FILE* pp)
{ p = pp; if (p==0) throw Open_error(errno); }
~File_handle() { fclose(p); }
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PostgreSQL - fetch the row which has the Max value for a column
...sted index lookup into lives - on my machine
-- the latter query plan was selected given my memory settings and
-- histogram
SELECT
l1.*
FROM
lives AS l1
INNER JOIN (
SELECT
usr_id,
MAX(time_stamp) AS time_stamp_max
FROM
lives
GROUP BY
usr_id
) AS l2
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extract part of a string using bash/cut/split
...gs based on position using numbers:
${MYVAR:3} # Remove the first three chars (leaving 4..end)
${MYVAR::3} # Return the first three characters
${MYVAR:3:5} # The next five characters after removing the first 3 (chars 4-9)
You can also replace particular strings or patterns using:
${MYVAR/sear...
(-2147483648> 0) returns true in C++?
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@RichardJ.RossIII - with clang you are probably getting a 64-bit-typed literal, since it was too big to fit in an int. OP's implementation may not have a 64-bit type.
– Carl Norum
Feb 4 '1...
How to select rows with no matching entry in another table?
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Here's a simple query:
SELECT t1.ID
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
WHERE t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
how do i remove a comma off the end of a string?
...sponding ltrim for left trim) is very useful as you can specify a range of characters to remove, i.e. to remove commas and trailing whitespace you would write:
$string = rtrim($string, ", \t\n");
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Linq code to select one item
I find myself writing a lot of code like this to select one item that matches
7 Answers
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