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Insert, on duplicate update in PostgreSQL?
...FLICT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group a...
How Many Seconds Between Two Dates?
...Z, NN, EE, 0, 0, 0, 0);
var dif = t1.getTime() - t2.getTime();
var Seconds_from_T1_to_T2 = dif / 1000;
var Seconds_Between_Dates = Math.abs(Seconds_from_T1_to_T2);
A handy source for future reference is the MDN site
Alternatively, if your dates come in a format javascript can parse
var dif = Da...
Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...tabase tables (instead of "dbo").
More importantly it will also prefix the __MigrationHistory table(s), e.g. Customer.__MigrationHistory.
So you can have more than one __MigrationHistory table in a single database, one for each context.
So the changes you make for one context will not mess with the ...
What is BSON and exactly how is it different from JSON?
...pes such as Date and binary which are not supported in JSON also provide ordered fields in order for it to be efficient for encoding and decoding within different languages.
In other word we can say BSON is just binary JSON ( a superset of JSON with some more data types, most importantl...
CSS: background image on background color
...nswered Jan 15 '18 at 17:12
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What are valid values for the id attribute in HTML?
...wed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").
HTML 5 is even more permissive, saying only that an id must contain at least one character and may not contain any space characters.
The id attribute is case sensitive in XHTML.
As a ...
Find where python is installed (if it isn't default dir)
...gt;>> sys.executable
'c:\\Python26\\python.exe'
>>> sys.exec_prefix
'c:\\Python26'
>>>
>>> print '\n'.join(sys.path)
c:\Python26\lib\site-packages\setuptools-0.6c11-py2.6.egg
c:\Python26\lib\site-packages\nose-1.0.0-py2.6.egg
C:\Windows\system32\python26.zip
c:\Pyth...
GetProperties() to return all properties for an interface inheritance hierarchy
...pe> instead of a Queue<>. With a stack, the ancestry maintains an order such that interface IFoo : IBar, IBaz where IBar : IBubble and 'IBaz : IFlubber, the order of reflection becomes: IBar, IBubble, IBaz, IFlubber, IFoo`.
– IAbstract
Oct 5 '14 at 16:...
Add list to set?
...rticle. Pythons hashing algorithms are explained on effbot.org and pythons __hash__ function in the python reference.
Some facts:
Set elements as well as dictionary keys have to be hashable
Some unhashable datatypes:
list: use tuple instead
set: use frozenset instead
dict: has no official count...
What are the differences between .so and .dylib on osx?
...between shared libraries and dynamically loaded modules. Use otool -hv some_file to see the filetype of some_file.
Mach-O shared libraries have the file type MH_DYLIB and carry the extension .dylib. They can be linked against with the usual static linker flags, e.g. -lfoo for libfoo.dylib. They ca...