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Set NOW() as Default Value for datetime datatype?
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it should work for updates too
Answers by Johan & Leonardo involve converting to a timestamp field. Although this is probably ok for the use case presented in the question (storing RegisterDate and LastVisitDate), it is not a universal solution. See datetime vs timestamp question.
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How to compare binary files to check if they are the same?
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I ended up using hexdump to convert the binary files to there hex representation and then opened them in meld / kompare / any other diff tool. Unlike you I was after the differences in the files.
hexdump tmp/Circle_24.png > tmp/hex1.txt
hexdump /tmp...
How can you do paging with NHibernate?
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ICriteria has a SetFirstResult(int i) method, which indicates the index of the first item that you wish to get (basically the first data row in your page).
It also has a SetMaxResults(int i) method, which indicates the number of rows you wish to get (i.e...
Calculate the number of business days between two dates?
...wer. Especially in the real world situation, when you have to examine time intervals of several months.
See my code, with comments, below.
/// <summary>
/// Calculates number of business days, taking into account:
/// - weekends (Saturdays and Sundays)
/// - bank holidays in...
How to randomly select rows in SQL?
...* FROM Table1
WHERE (ABS(CAST(
(BINARY_CHECKSUM
(keycol1, NEWID())) as int))
% 100) < 10
https://msdn.microsoft.com/en-us/library/cc441928.aspx
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Cannot use ref or out parameter in lambda expressions
... can be accessed after the method frame is no longer on the stack
Func<int> Example(int p1) {
return () => p1;
}
Another property of captured variables is that changes to the variable are also visible outside the lambda expression. For example the following prints 42
void Example2(in...
Deleting elements from std::set while iterating
...get to the temp. For example, re-write your loop as follows:
std::set<int>::iterator it = numbers.begin();
std::set<int>::iterator tmp;
// iterate through the set and erase all even numbers ...
What does the unary plus operator do?
...erator itself. For example, it can be used to force widening from smaller integral types to int, or ensure that an expression's result is treated as an rvalue and therefore not compatible with a non-const reference parameter. I submit, however, that these uses are better suited to code golf than r...
Can a recursive function be inline?
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First, the inline specification on a function is just a hint. The compiler can (and often does) completely ignore the presence or absence of an inline qualifier. With that said, a compiler can inline a recursive function, much as it can unroll an infinite loop. It simply has to ...
Can table columns with a Foreign Key be NULL?
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Yes, you can enforce the constraint only when the value is not NULL. This can be easily tested with the following example:
CREATE DATABASE t;
USE t;
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE...