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Spring @Transactional - isolation, propagation
... | |
rollback |
v v
value (x) is now dirty (incorrect)
So a sane default (if such can be claimed) could be Read Committed, which only lets you read values which have already been committed by other running transactions, in combination with a propagation le...
Efficiently convert rows to columns in sql server
...nt, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you want to transpose, then you can use dynamic SQL:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',...
Why do we need a pure virtual destructor in C++?
...class Base
{
public:
Base();
virtual ~Base() = 0; // Pure virtual, now no one can create the Base Object directly
};
Base::Base() { cout << "Base Constructor" << endl; }
Base::~Base() { cout << "Base Destructor" << endl; }
class Derived : public Base
{
public:
...
Draw radius around a point in Google map
I'm using the Google Maps API and have added markers. Now I want to add a 10 mile radius around each marker, meaning a circle that behaves appropriately while zooming. I have no idea how to do that and it seems it's not something common.
...
Named regular expression group “(?Pregexp)”: what does “P” stand for?
...Perl 5; O'Reilly
publishes books about both languages.)
As you may know, Python 1.5 adds a new regular expression module that
more closely matches Perl's syntax. We've tried to be as close to the
Perl syntax as possible within Python's syntax. However, the regex
syntax has some Python...
Ignore Xcode warnings when using Cocoapods
... in it, after the latest Xcode updates. (for example the Facebook SDK pod)
Now all these warnings are shown in my Xcode on the place I want to see my own warnings or errors.
...
MVC DateTime binding with incorrect date format
Asp.net-MVC now allows for implicit binding of DateTime objects. I have an action along the lines of
10 Answers
...
Can Java 8 code be compiled to run on Java 7 JVM?
...
Now I see: Your "No" answers the question's headline, not the question's body.
– Abdull
Oct 28 '14 at 17:37
...
What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
... I was just playing with something like that on a bit of paper, right now looks fairly optimal in most cases, even without rotating the rectangles or anything
– Fire Lancer
Jul 31 '09 at 16:37
...
What can I do to resolve a “Row not found or changed” Exception in LINQ to SQL on a SQL Server Compa
...pping, LINQ will load it successfully and set the column-String to null.
Now you change something and call
SubmitChanges().
LINQ will generate a SQL query
containing "WHERE [title] IS NULL", to make sure the title has not been changed by someone else.
LINQ looks up the properties of
[title] in the...