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Oracle “Partition By” Keyword
...t_no DEPT_COUNT
1 10 3
2 10 3
3 10 3 <- three because there are three "dept_no = 10" records
4 20 2
5 20 2 <- two because there are two "dept_no = 20" records
If there was another column (e.g., state) then you could count how many ...
Set Django IntegerField by choices=… name
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I have a problem: I always see the default value on the admin! I have tested that the value really changes! What should I do now?
– Mahdi
Dec 13 '13 at 18:59
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How to Compare Flags in C#?
...in the simplest of cases, the Enum.HasFlag carries a heavy performance penalty in comparison to writing out the code manually. Consider the following code:
[Flags]
public enum TestFlags
{
One = 1,
Two = 2,
Three = 4,
Four = 8,
Five = 16,
Six = 32,
Seven = 64,
Eight ...
Difference between final and effectively final
...Number constructor:
public class OutterClass {
int numberLength; // <== not *final*
class PhoneNumber {
PhoneNumber(String phoneNumber) {
numberLength = 7; // <== assignment to numberLength
String currentNumber = phoneNumber.replaceAll(
regularExpres...
How to read a large file - line by line?
...ine of interest. This method uses a lot of memory, so I am looking for an alternative.
11 Answers
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How do I adjust the anchor point of a CALayer, when Auto Layout is being used?
...to mess with the frame of a view that has a transform (other than the default identity transform) - but that is exactly what autolayout does. The way autolayout works is that in layoutSubviews the runtime comes dashing through all the constraints and setting the frames of all the views accordingly.
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What's wrong with this 1988 C code?
...like:
if (c == ' ' || c == '\n' || c == '\t')
state = 0;; /* <--PROBLEM #1 */
else if (state == 0;) { /* <--PROBLEM #2 */
state = 1;;
That second semicolon causes the else to have no previous if as a match, because you are not using braces. So, remove the semicolons ...
INNER JOIN vs LEFT JOIN performance in SQL Server
...ll the work of an INNER JOIN plus the extra work of null-extending the results. It would also be expected to return more rows, further increasing the total execution time simply due to the larger size of the result set.
(And even if a LEFT JOIN were faster in specific situations due to some diffic...
Can I invoke an instance method on a Ruby module without including it?
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I think the shortest way to do just throw-away single call (without altering existing modules or creating new ones) would be as follows:
Class.new.extend(UsefulThings).get_file
share
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impro...
How to toggle a value in Python
...the values are boolean, the fastest approach is to use the not operator:
>>> x = True
>>> x = not x # toggle
>>> x
False
>>> x = not x # toggle
>>> x
True
>>> x = not x # toggle
>>> x
False
Solution using subtract...