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Can table columns with a Foreign Key be NULL?
...ue to NULL when INSERTING or UPDATING, you're good to go.
But this is the fun of programming, isn't it? Creating our own problems and then fixing them! Cheers!
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How to convert int to QString?
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123
And if you want to put it into string within some text context, forget about + operator.
Simp...
append multiple values for one key in a dictionary [duplicate]
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python way is to not duplicate functionality
– SilentGhost
Jul 9 '10 at 12:59
2
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What's the u prefix in a Python string?
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That was a fun read! Thanks! Article is 17 years old and it's still accurate. Wow.
– Kerwin Sneijders
Feb 28 at 11:08
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Use of alloc init instead of new
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Very old question, but I've written some example just for fun — maybe you'll find it useful ;)
#import "InitAllocNewTest.h"
@implementation InitAllocNewTest
+(id)alloc{
NSLog(@"Allocating...");
return [super alloc];
}
-(id)init{
NSLog(@"Initializing...");
retur...
MySQL Query to select data from last week?
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SELECT id FROM tbl
WHERE date >= curdate() - INTERVAL DAYOFWEEK(curdate())+6 DAY
AND date &...
How to copy a collection from one database to another in MongoDB
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You could do something like:
db.<collection_name>.find().forEach(function(d){ db.getSiblingDB('<new_database>')['<collection_name>'].insert(d); });
Please note that with this, the two databases would need to share the same mongod for this to work.
Besides this, you can do a...
Are +0 and -0 the same?
... Actually, this behavior models limit calculation in math. For example function 1/x has a value infinity in 0, however, it is separated if we are approaching 0 from the positive of negative side; in the former, the result is +inf, in the latter, -inf.
– Agoston Horvath
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Suppress warning messages using mysql from within Terminal, but password written in bash script
... edited Aug 4 at 7:44
coding is fun
35677 silver badges1515 bronze badges
answered Apr 8 '14 at 9:34
David Goo...
Associative arrays in Shell scripts
...e ugliest of hacks.
For a verbose, detailed answer with example code see:
https://stackoverflow.com/questions/3467959
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