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What are the main performance differences between varchar and nvarchar SQL Server data types?
... most applications. However, if you need to support double-byte languages and you only have single-byte support in your database schema it's really expensive to go back and modify throughout your application.
The cost of migrating one application from varchar to nvarchar will be much more than t...
Null vs. False vs. 0 in PHP
...m told that good developers can spot/utilize the difference between Null and False and 0 and all the other good "nothing" entities.
What is the difference, specifically in PHP? Does it have something to do with === ?
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Which is the fastest algorithm to find prime numbers?
...ly I don't think primegen is the fastest, or even the second-fastest; yafu and primesieve are both faster in general, I think, and certainly over 2^32. Both are (modified) sieves of Eratosthenes rather than the Atkin-Bernstein sieve.
– Charles
Aug 19 '11 at 4:...
How to check if a table exists in a given schema
Postgres 8.4 and greater databases contain common tables in public schema and company specific tables in company schema.
company schema names always start with 'company' and end with the company number.
So there may be schemas like:
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How can you determine a point is between two other points on a line segment?
Let's say you have a two dimensional plane with 2 points (called a and b) on it represented by an x integer and a y integer for each point.
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Check if full path given
... @SmirkinGherkin so what is the difference between a rooted and absolute path?
– Jason Axelson
Mar 1 '13 at 1:23
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
What is the difference between == and === in PHP?
11 Answers
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Bad class file magic or version
I already know that question has been already asked very often and answers, but no one of the answers i found fixed my problem.
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Enabling WiFi on Android Emulator
How to enable WiFi on Android emulator? I have tried to find this but everyone is confusing WiFi with 3G.
6 Answers
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What are the underlying data structures used for Redis?
...every Redis operation you'll find the time complexity in the documentation and, if you have the set of operations and the time complexity, the only other thing you need is some clue about memory usage (and because we do many optimizations that may vary depending on data, the best way to get these la...