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Possible to do a MySQL foreign key to one of two possible tables?
...which target table is referenced.
CREATE TABLE popular_places (
user_id INT NOT NULL,
place_id INT NOT NULL,
place_type VARCHAR(10) -- either 'states' or 'countries'
-- foreign key is not possible
);
There's no way to model Polymorphic Associations using SQL constraints. A foreign key co...
Use of 'const' for function parameters
...lot though.
I personally tend to not use const except for reference and pointer parameters. For copied objects it doesn't really matter, although it can be safer as it signals intent within the function. It's really a judgement call. I do tend to use const_iterator though when looping on something ...
Return from lambda forEach() in java
... case it will be streams, lambdas and method references.
You should never convert existing code to Java 8 code on a line-by-line basis, you should extract features and convert those.
What I identified in your first case is the following:
You want to add elements of an input structure to an outpu...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...he x86, misaligned accesses are handled in hardware; if you dereference an int* pointer that points to an odd address, it will be a little slower than if it were properly aligned, but you'll get the correct result.)
On some other systems, such as SPARC, attempting to access a misaligned int object ...
Why does an image captured using camera intent gets rotated on some devices on Android?
...o it will work in most cases, but it is not a 100% reliable solution.
ExifInterface ei = new ExifInterface(photoPath);
int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_UNDEFINED);
Bitmap rotatedBitmap = null;
switch(...
How do I perform an insert and return inserted identity with Dapper?
...his case the simpler option is simply:
var id = connection.QuerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff]) VALUES (@Stuff);
SELECT CAST(SCOPE_IDENTITY() as int)", new { Stuff = mystuff});
Note that on more recent versions of SQL Server you can use the OUTPUT clause:
var id = connectio...
Array_merge versus + [duplicate]
..., array_merge() concat index-array values.
If not, the index-array will to convert to values array, and then convert to assoc array.
Now it got two assoc array and merge them together, when key conflict, right(last) value will be kept.
array_merge(null, array()) returns array() and got a warning sai...
Best way to merge two maps and sum the values of same key?
...al map1 = Map(1 -> 9 , 2 -> 20)
map1: scala.collection.immutable.Map[Int,Int] = Map(1 -> 9, 2 -> 20)
scala> val map2 = Map(1 -> 100, 3 -> 300)
map2: scala.collection.immutable.Map[Int,Int] = Map(1 -> 100, 3 -> 300)
scala> map1 |+| map2
res2: scala.collection.immutable...
HashMap and int as key
I am trying to build a HashMap which will have integer as keys and objects as values.
11 Answers
...
Types in Objective-C on iOS
... NSLog(@"The size of short is: %d.", sizeof(short));
NSLog(@"The size of int is: %d.", sizeof(int));
NSLog(@"The size of long is: %d.", sizeof(long));
NSLog(@"The size of long long is: %d.", sizeof(long long));
NSLog(@"The size of a unsigned char is: %d.", sizeof(unsigned char));
NSLog(@"T...