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Why does NULL = NULL evaluate to false in SQL server
... part number code in
Inventory that is referenced as a FOREIGN KEY by an Orders table, you
will have problems getting a listing of the parts that have a NULL. This is
a mandatory relationship; you cannot order a part that does not exist.
(separator)
6.9.1 Avoiding NULLs from the Host Pro...
How to use single storyboard uiviewcontroller for multiple subclass
...
The code of line we are looking for is:
object_setClass(AnyObject!, AnyClass!)
In Storyboard -> add UIViewController give it a ParentVC class name.
class ParentVC: UIViewController {
var type: Int?
override func awakeFromNib() {
if type = 0 {
...
What is a “thread” (really)?
...struction Pointer (aka Program Counter), it controls what executes in what order. It also includes the Stack Pointer, which had better point to a unique area of memory for each thread or else they will interfere with each other.
Threads are the software unit affected by control flow (function call...
What is the difference between named and positional parameters in Dart?
...
Because named parameters are referenced by name, they can be used in an order different from their declaration.
getHttpUrl('example.com', '/index.html');
getHttpUrl('example.com', '/index.html', port: 8080);
getHttpUrl('example.com', '/index.html', port: 8080, numRetries: 5);
getHttpUrl('example...
Rearrange columns using cut
...anges separated by commas. Selected input is written
in the same order that it is read, and is written exactly once.
It reaches field 1 first, so that is printed, followed by field 2.
Use awk instead:
awk '{ print $2 " " $1}' file.txt
...
java.lang.ClassNotFoundException: Didn't find class on path: dexpathlist
...nstant Run is still so buggy to the extend that you have to turn it off in order to avoid nasty surprises...
– Ognyan
Oct 1 '17 at 10:54
2
...
Best practice using NSLocalizedString
...our string files, discarding all your previous translations.
I wrote update_strings.py to parse the old strings file, run genstrings and fill in the blanks so that you don't have to manually restore your existing translations.
The script tries to match the existing string files as closely as possibl...
Passing functions with arguments to another function in Python?
... y):
return x+y
# declare partial function
def addPartial(x):
def _wrapper(y):
return add(x, y)
return _wrapper
# run example
def main():
f = addPartial(3)
result = runOp(f, 1) # is 4
Use partial from functools
This is almost identical to lambda shown above. Then why...
nvarchar(max) vs NText
...name, column_name
FROM information_schema.columns where data_type = 'TEXT' order by table_name, column_name
SELECT concat('ALTER TABLE dbo.[', table_name, '] ALTER COLUMN [', column_name, '] NVARCHAR(MAX)'), table_name, column_name
FROM information_schema.columns where data_type = 'NTEXT' order by ...
What is the difference between return and return()?
...allowed because they are allowed in any expression to influence evaluation order, but in your examples they're just superfluous.
return is not a function, but a statement. It is syntactically similar to other simple control flow statements like break and continue that don't use parentheses either.
...