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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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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:...
Ignoring time zones altogether in Rails and PostgreSQL
I'm dealing with dates and times in Rails and Postgres and running into this issue:
2 Answers
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Cookies vs. sessions
...r the sake of creating a login system for my website, I read about cookies and sessions and their differences (cookies are stored in the user's browser and sessions on the server). At that time, I preferred cookies (and who does not like cookies?!) and just said: "who cares? I don't have any good de...
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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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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Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
I tested the above code in Chrome's console and for some reason, a() returns true, b() returns true, and c() returns false.
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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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PreparedStatement IN clause alternatives?
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An analysis of the various options available, and the pros and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one pre...
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...