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Efficiently convert rows to columns in sql server
...######################
--###| Step 2 - Preparing lists of column groups as strings:
--#######################################################################################################################
DECLARE @ColumnName nvarchar(128)
DECLARE @Destiny ...
What's the difference between ViewData and ViewBag?
...e same way as viewdata should be avoided).
So basically it replaces magic strings:
ViewData["Foo"]
with magic properties:
ViewBag.Foo
for which you have no compile time safety.
I continue to blame Microsoft for ever introducing this concept in MVC.
The name of the properties are case sensit...
How to check Django version
... to make sure that '1.7' < '1.7.1' < '1.7.5' < '1.7.10'. A normal string comparison would fail in the last comparison:
>>> '1.7.5' < '1.7.10'
False
The solution is to use StrictVersion from distutils.
>>> from distutils.version import StrictVersion
>>> Stri...
Difference between objectForKey and valueForKey?
...ndexes, it uses keys to differentiate between items. A key is an arbitrary string you provide. No two objects can have the same key (just as no two objects in an NSArray can have the same index).
valueForKey: is a KVC method. It works with ANY class. valueForKey: allows you to access a property us...
How do I create a unique ID in Java? [duplicate]
I'm looking for the best way to create a unique ID as a String in Java.
11 Answers
11
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Git: How to squash all commits on branch
... needs, you can reset with origin/master as well). This will reset all the extra commits in your feature_branch, but without changing any of your file changes locally.
git reset --soft master
Step 2:
Add all of the changes in your git repo directory, to the new commit that is going to be created. A...
How can I calculate the difference between two dates?
...
NSDate *date1 = [NSDate dateWithString:@"2010-01-01 00:00:00 +0000"];
NSDate *date2 = [NSDate dateWithString:@"2010-02-03 00:00:00 +0000"];
NSTimeInterval secondsBetween = [date2 timeIntervalSinceDate:date1];
int numberOfDays = secondsBetween / 86400;
NS...
What's the difference between the atomic and nonatomic attributes?
...e dependent properties are in play.
Consider:
@property(atomic, copy) NSString *firstName;
@property(atomic, copy) NSString *lastName;
@property(readonly, atomic, copy) NSString *fullName;
In this case, thread A could be renaming the object by calling setFirstName: and then calling setLastNam...
Inserting string at position x of another string
I have two variables and need to insert string b into string a at the point represented by position . The result I'm looking for is "I want an apple". How can I do this with JavaScript?
...
Replace all 0 values to NA
... "complete.obs". Typically, however, this is unsatisfactory as it leads to extra information loss.
2. Instead of running some sort of loop, in the solution I use df == 0 vectorization. df == 0 returns (try it) a matrix of the same size as df, with the entries TRUE and FALSE. Further, we are also al...