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MySQL: multiple tables or one table with many columns?
...ple the date-of-birth of a user will not be updated ever, but the back end token may be invalidated after a period of time and will require frequent updates. Would it be better if I separate the tables in this manner to improve the performance? I'll now go read about the wiki that you mentioned :)
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How to convert a string into double and vice versa?
...separators, also.
NSNumberFormatter * myNumFormatter = [[NSNumberFormatter alloc] init];
[myNumFormatter setLocale:[NSLocale currentLocale]]; // happen by default?
[myNumFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
// next line is very important!
[myNumFormatter setNumberStyle...
Difference between fprintf, printf and sprintf?
...dout)
fprintf goes to a file handle (FILE*)
sprintf goes to a buffer you allocated. (char*)
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When should I use nil and NULL in Objective-C?
...e object. Let's have an example:
NSMutableArray *check = [[NSMutableArray alloc] init];
[check addObject:[NSNull null]];
[check addObject:nil];
On the second line, we will not get any error, because it is perfectly fair to insert a NSNull object into a collection type object. On the third line, w...
What does the “at” (@) symbol do in Python?
...tors, which includes @, which makes it also an operator:
The following tokens are operators:
+ - * ** / // % @
<< >> & | ^ ~
< > <= >= == !=
and in the next page, the Dat...
Maximum size of an Array in Javascript
...a big deal
x=3e7 takes 1300ms, which is pretty bad
x=4e7 takes 11000ms and allocates an extra 2.5GB of memory
So around 30 million elements is a hard upper limit, because the javascript VM falls off a cliff at 40 million elements and will probably crash the process.
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How do I quickly rename a MySQL database (change schema name)?
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I think the solution is simpler and was suggested by some developers. phpMyAdmin has an operation for this.
From phpMyAdmin, select the database you want to select. In the tabs there's one called Operations, go to the rename section. That's all.
It does, as many suggested, create a new databa...
Generate a random alphanumeric string in Cocoa
... genRandStringLength should just return randomString. There's no reason to alloc and init (and not autorelease!) a whole new string.
– kevingessner
Apr 14 '10 at 0:49
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Difference between the Apache HTTP Server and Apache Tomcat? [closed]
...r. A servlet, at the end, is a Java class. JSP files (which are similar to PHP, and older ASP files) are generated into Java code (HttpServlet), which is then compiled to .class files by the server and executed by the Java virtual machine.
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Why (0-6) is -6 = False? [duplicate]
... is an array of 262 pointers to integer objects. Those integer objects are allocated during initialization in a block of integer objects we saw above. The small integers range is from -5 to 256. Many Python programs spend a lot of time using integers in that range so this is a smart decision.
This...