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What's the difference between session.persist() and session.save() in Hibernate?
...also guarantees that it will
not execute an INSERT statement if it
is called outside of transaction
boundaries. This is useful in
long-running conversations with an
extended Session/persistence context.
A method like persist() is required.
save() does not guarantee the same, it...
Index of Currently Selected Row in DataGridView
...ndex error two. You'd better wrapped it with a if
– Allan Ruin
Mar 11 '15 at 1:22
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Adding days to $Date in PHP
...
All you have to do is use days instead of day like this:
<?php
$Date = "2010-09-17";
echo date('Y-m-d', strtotime($Date. ' + 1 days'));
echo date('Y-m-d', strtotime($Date. ' + 2 days'));
?>
And it outputs correctly:
...
Multi-line commands in GHCi
...he following is sufficient:
Prelude> let addTwo x y = x + y
If you really want a definition with a type signature, or your definition spans over multiple lines, you can do this in ghci:
Prelude> :{
Prelude| let addTwo :: Int -> Int -> Int
Prelude| addTwo x y = x + y
Prelude| :}
...
Why can't I have abstract static methods in C#?
...tantiated as such, they're just available without an object reference.
A call to a static method is done through the class name, not through an object reference, and the Intermediate Language (IL) code to call it will call the abstract method through the name of the class that defined it, not neces...
Why do we need the “event” keyword while defining events?
...-like events and public fields of delegate types look similar, but are actually very different.
An event is fundamentally like a property - it's a pair of add/remove methods (instead of the get/set of a property). When you declare a field-like event (i.e. one where you don't specify the add/remove ...
Is it better to return null or empty collection?
...llection might mean "0 items", returning Null could mean "no collection at all" - eg. if you are parsing HTML, looking for an <ul> with id="foo", <ul id="foo"></ul> could return empty collection; if there is no <ul> with id="foo" a null return would be better (unless you want...
Select last row in MySQL
...
Yes, there's an auto_increment in there
If you want the last of all the rows in the table, then this is finally the time where MAX(id) is the right answer! Kind of:
SELECT fields FROM table ORDER BY id DESC LIMIT 1;
...
Why is rbindlist “better” than rbind?
...
rbindlist is an optimized version of do.call(rbind, list(...)), which is known for being slow when using rbind.data.frame
Where does it really excel
Some questions that show where rbindlist shines are
Fast vectorized merge of list of data.frames by row
Trouble...
convert string array to string
...tringArrayToString(string[] array)
{
//
// Concatenate all the elements into a StringBuilder.
//
StringBuilder strinbuilder = new StringBuilder();
foreach (string value in array)
{
strinbuilder.Append(value);
strinbuilder.Ap...