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Why does NULL = NULL evaluate to false in SQL server
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Neil McGuiganNeil McGuigan
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Possible to do a MySQL foreign key to one of two possible tables?
...es (
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 constraint always references one target table.
Polymorphic As...
Java naming convention for static final variables [duplicate]
... ..."
– Andy Thomas
Sep 1 '11 at 20:10
1
They are fields themselves, so why should obscuring a fi...
Does PHP have threading?
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Here is an example of what Wilco suggested:
$cmd = 'nohup nice -n 10 /usr/bin/php -c /path/to/php.ini -f /path/to/php/file.php action=generate var1_id=23 var2_id=35 gen_id=535 > /path/to/log/file.log & echo $!';
$pid = shell_exec($cmd);
Basically this executes the PHP script at the...
How expensive is RTTI?
...ge in runtime memory usage.
A quick experiment (using GCC 4.4.3 on Ubuntu 10.04 64-bit) shows that -fno-rtti actually increases the binary size of a simple test program by a few hundred bytes. This happens consistently across combinations of -g and -O3. I'm not sure why the size would increase; one...
Do you (really) write exception safe code? [closed]
...?
Writing exception-safe code is like writing bug-free code.
You can't be 100% sure your code is exception safe. But then, you strive for it, using well-known patterns, and avoiding well-known anti-patterns.
Do you know and/or actually use alternatives that work?
There are no viable alternatives ...
Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
...tling backward and forward containing the integers.
Once COUNTER reaches 1000000, you have all of the values stored in the incessant stream of ICMP requests, and VALUE now contains the maximum integer. Pick some threshold T >> 1000000. Set COUNTER to zero. Every time you receive an ICMP pack...
Android ListView headers
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+100
Here's how I do it, the keys are getItemViewType and getViewTypeCount in the Adapter class. getViewTypeCount returns how many types...
How does Access-Control-Allow-Origin header work?
...DomainB.com
User-Agent Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0) Gecko/20100101 Firefox/4.0
Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8,application/json
Accept-Language en-us;
Accept-Encoding gzip, deflate
Keep-Alive 115
Origin http://DomainA.com
DomainB response head...
SPA best practices for authentication and session management
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edited May 13 at 10:11
kovalyovi
33933 silver badges99 bronze badges
answered Jan 16 '14 at 23:...