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Fast way to discover the row count of a table in PostgreSQL
I need to know the number of rows in a table to calculate a percentage. If the total count is greater than some predefined constant, I will use the constant value. Otherwise, I will use the actual number of rows.
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Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
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How do Trigonometric functions work?
So in high school math, and probably college, we are taught how to use trig functions, what they do, and what kinds of problems they solve. But they have always been presented to me as a black box. If you need the Sine or Cosine of something, you hit the sin or cos button on your calculator and you'...
How to detect a Christmas Tree? [closed]
Which image processing techniques could be used to implement an application that detects the Christmas trees displayed in the following images?
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Build an iOS app without owning a mac? [closed]
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Let me tell you step by step few years back I was in same situation.
So We have two Phases
iPhone/iPad (iOS) app development
iPhone/iPad (iOS) app development and Publish to iTunes Store
1. iPhone/iPad (iOS) app development
So If you just want to develop iOS apps you d...
How do you generate dynamic (parameterized) unit tests in python?
I have some kind of test data and want to create a unit test for each item. My first idea was to do it like this:
25 Answer...
Assign output of a program to a variable using a MS batch file
I need to assign the output of a program to a variable using a MS batch file.
9 Answers
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“To Do” list before publishing Android app to market [closed]
...if any of you have any tips about any experiences you may have encountered in regard to publishing an app that goes beyond the obvious and already documented.
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Haskell Type vs Data Constructor
I am learning Haskell from learnyouahaskell.com . I am having trouble understanding type constructors and data constructors. For example, I don't really understand the difference between this:
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How to generate a random number in C++?
I'm trying to make a game with dice, and I need to have random numbers in it (to simulate the sides of the die. I know how to make it between 1 and 6). Using
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