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Difference between one-to-many and many-to-one relationship
...) has only 1 order for $158.01.
What is important to realize is that typically the one-to-many relationship doesn't actually add any columns to the table that is the "one". The Customer has no extra columns which describe the relationship with Order. In fact the Customer might also have a one-to-...
Disabling implicit animations in -[CALayer setNeedsDisplayInRect:]
...like you can specify any key you could use in setValue:forKey: method, actually specifying complex key paths like bounds.size.
– pqnet
Apr 8 '12 at 17:41
13
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MySQL: Large VARCHAR vs. TEXT?
...ords messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserted into the db as longer than this.
...
Why are C character literals ints instead of chars?
...
discussion on same subject
"More specifically the integral promotions. In K&R C it was virtually (?)
impossible to use a character value without it being promoted to int first,
so making character constant int in the first place eliminated that step.
There...
How does the new automatic reference counting mechanism work?
...rty assignments are inexpensive (as discussed here). I know I'm replacing all of my existing Mac GC code with ARC implementations.
As to whether this could be extended to other languages, it seems geared around the reference counting system in Objective-C. It might be difficult to apply this to J...
How/When does Execute Shell mark a build as failure in Jenkins?
...e said:
If you have a shell script that does "checkout, build, deploy" all by itself, then why are you using Jenkins? You are foregoing all the features of Jenkins that make it what it is. You might as well have a cron or an SVN post-commit hook call the script directly. Jenkins performing the S...
What's the function like sum() but for multiplication? product()?
...Older info: Python 3.7 and prior
The function you're looking for would be called prod() or product() but Python doesn't have that function. So, you need to write your own (which is easy).
Pronouncement on prod()
Yes, that's right. Guido rejected the idea for a built-in prod() function because he t...
mailto link with HTML body
...
As you can see in RFC 6068, this is not possible at all:
The special <hfname> "body" indicates that the associated <hfvalue>
is the body of the message. The "body" field value is intended to
contain the content for the first text/plain body part of the
m...
Qt events and signal/slots
... and handled by
any instance of a QObject subclass,
but they are especially relevant to
widgets. This document describes how
events are delivered and handled in a
typical application.
So events and signal/slots are two parallel mechanisms accomplishing the same things. In general, an eve...
Why must wait() always be in synchronized block
We all know that in order to invoke Object.wait() , this call must be placed in synchronized block, otherwise an IllegalMonitorStateException is thrown. But what's the reason for making this restriction? I know that wait() releases the monitor, but why do we need to explicitly acquire the mon...