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Adding multiple columns AFTER a specific column in MySQL
...
If you want to add a single column after a specific field, then the following MySQL query should work:
ALTER TABLE users
ADD COLUMN count SMALLINT(6) NOT NULL
AFTER lastname
If you want to add multiple columns, then ...
What's the UIScrollView contentInset property for?
...ew.
Obj-C
aScrollView.contentInset = UIEdgeInsetsMake(0, 0, 0, 7.0);
Swift 5.0
aScrollView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 7.0)
Here's a good iOS Reference Library article on scroll views that has an informative screenshot (fig 1-3) - I'll replicate it via text ...
Why doesn't Objective-C support private methods?
...here and in other questions), compile-time private methods are supported; if a class doesn't declare a method in its publicly available interface, then that method might as well not exist as far as your code is concerned. In other words, you can achieve all of the various combinations of visibilit...
What is the difference between ? and Object in Java generics?
...Say you want to write a method that accepts maps from Strings to anything: If you would write
public void foobar(Map<String, Object> ms) {
...
}
you can't supply a HashMap<String, String>. If you write
public void foobar(Map<String, ?> ms) {
...
}
it works!
A thing s...
Where's the difference between setObject:forKey: and setValue:forKey: in NSMutableDictionary?
When looking at the documentation, I hardly see any big difference. Both "value" and "object" are of type id , so can be any object. Key is once a string, and in the other case an id. One of them seems to retain the object, and the other don't. What else? Which one is for what case?
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What's the function like sum() but for multiplication? product()?
... in Python 3, the reduce() function was moved to the functools module.
Specific case: Factorials
As a side note, the primary motivating use case for prod() is to compute factorials. We already have support for that in the math module:
>>> import math
>>> math.factorial(10)
362880...
Execution time of C program
... 60ms.
clock() is standard C; it works "everywhere". There are system-specific functions, such as getrusage() on Unix-like systems.
Java's System.currentTimeMillis() does not measure the same thing. It is a "wall clock": it can help you measure how much time it took for the program to execute, but...
Dynamically adding properties to an ExpandoObject
... would copy it to a dictionary. However, your post made me understand that if you change the Dictionary, you also change the underlying ExpandoObject! Thanks a lot
– Dynalon
Jan 27 '12 at 18:48
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html - table row like a link
...t my table row as link to something. I can use only css and html. I tried different things from div in row to something another, but still can't make it works.
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Postgres and Indexes on Foreign Keys and Primary Keys
... columns.
Therefore you have to create indexes on foreign-keys yourself if you want them.
Note that if you use primary-foreign-keys, like 2 FK's as a PK in a M-to-N table, you will have an index on the PK and probably don't need to create any extra indexes.
While it's usually a good idea to cre...