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Best practices for in-app database migration for Sqlite
I am using sqlite for my iphone and I anticipate the database schema might change over time. What are the gotchas, naming conventions and things to watch out for to do a successful migration each time?
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Does Java 8 provide a good way to repeat a value or function?
...- 1)
.forEach(System.out::println);
Or build a custom iteration and limit the size of the iteration:
IntStream.iterate(1, i -> i + 2)
.limit(8)
.forEach(System.out::println);
share
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Codeigniter - no input file specified
I am a beginner in Codeigniter and I saw a CI tutorial and was just trying to do a simple thing. I downloaded the CI and added this file to controller directory, but it won't work.
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Regex lookahead, lookbehind and atomic groups
...hat I can use them for.
Does somebody have examples so I can try to understand how they work?
3 Answers
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Difference between Pragma and Cache-Control headers?
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Pragma is the HTTP/1.0 implementation and cache-control is the HTTP/1.1 implementation of the same concept. They both are meant to prevent the client from caching the response. Older clients may not support HTTP/1.1 which is why that header is still in use.
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Difference between dispatch_async and dispatch_sync on serial queue?
...k is finished whereas dispatch_async return after it is added to the queue and may not finished.
for this code
dispatch_async(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_async(_serialQueue, ^{ printf("3"); });
printf("4");
It may print 2413 or 2143 or 1234 but 1 always before 3
for ...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
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Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# ...
Remove duplicate values from JS array [duplicate]
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Quick and dirty using jQuery:
var names = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"];
var uniqueNames = [];
$.each(names, function(i, el){
if($.inArray(el, uniqueNames) === -1) uniqueNames.push(el);
});
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Cartesian product of x and y array points into single array of 2D points
I have two numpy arrays that define the x and y axes of a grid. For example:
13 Answers
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Difference between “and” and && in Ruby?
What is the difference between the && and and operators in Ruby?
7 Answers
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