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Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
...----- -------- -------------------------
0xCD Clean Memory Allocated memory via malloc or new but never
written by the application.
0xDD Dead Memory Memory that has been released with delete or free.
It is used to detect w...
How can I selectively merge or pick changes from another branch in Git?
I'm using Git on a new project that has two parallel -- but currently experimental -- development branches:
25 Answers
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C# pattern to prevent an event handler hooked twice [duplicate]
...ution and the best one (considering performance) is:
private EventHandler _foo;
public event EventHandler Foo {
add {
_foo -= value;
_foo += value;
}
remove {
_foo -= value;
}
}
No Linq using required. No need to check for null before cancelling a subscrip...
What are 'closures' in .NET?
...thod and the variable j
[CompilerGenerated]
private sealed class <>c__DisplayClass2
{
public <>c__DisplayClass2();
public void <fillFunc>b__0()
{
Console.Write("{0} ", this.j);
}
public int j;
}
for the function:
static void fillFunc(int count) {
...
How do I trim leading/trailing whitespace in a standard way?
... C? I'd roll my own, but I would think this is a common problem with an equally common solution.
38 Answers
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MySQL OPTIMIZE all tables?
...ZE TABLE command which can be used to reclaim unused space in a MySQL install. Is there a way (built-in command or common stored procedure) to run this optimization for every table in the database and/or server install, or is this something you'd have to script up yourself?
...
What is the result of % in Python?
...s second operand (or zero); the absolute value of the result is strictly smaller than the absolute value of the second operand [2].
Taken from http://docs.python.org/reference/expressions.html
Example 1:
6%2 evaluates to 0 because there's no remainder if 6 is divided by 2 ( 3 times ).
Example 2...
load scripts asynchronously
...time to load. it will be nice if I can display the loader before importing all the:
19 Answers
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Why can't Python parse this JSON data?
... You have [] when you should have {}:
[] are for JSON arrays, which are called list in Python
{} are for JSON objects, which are called dict in Python
Here's how your JSON file should look:
{
"maps": [
{
"id": "blabla",
"iscategorical": "0"
},
...